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Search results for tag #astronomy

[?]grobi » 🌐
@grobi@defcon.social

15/12/2021

ExoMars discovers hidden water in Mars’ Grand Canyon

The ESA-Roscosmos ExoMars Trace Gas Orbiter has spotted significant amounts of water at the heart of Mars’ dramatic canyon system, Valles Marineris in 2021.

The water, which is hidden beneath Mars’ surface, was found by the Trace Gas Orbiter (TGO)’s FREND instrument, which is mapping the hydrogen – a measure of water content – in the uppermost metre of Mars’ soil.

While water is known to exist on Mars, most is found in the planet’s cold polar regions as ice. Water ice is not found exposed at the surface near the equator, as temperatures here are not cold enough for exposed water ice to be stable.

Missions including ESA’s Mars Express have hunted for near-surface water – as ice covering dust grains in the soil, or locked up in minerals – at lower latitudes of Mars, and found small amounts. However, such studies have only explored the very surface of the planet; deeper water stores could exist, covered by dust.

“With TGO we can look down to one metre below this dusty layer and see what’s really going on below Mars’ surface – and, crucially, locate water-rich ‘oases’ that couldn’t be detected with previous instruments,” says Igor Mitrofanov of the Space Research Institute in Moscow, Russia.

“FREND revealed an area with an unusually large amount of hydrogen in the colossal Valles Marineris canyon system: assuming the hydrogen we see is bound into water molecules, as much as 40% of the near-surface material in this region appears to be water.”

The water-rich area is about the size of the Netherlands and overlaps with the deep valleys of Candor Chaos, part of the canyon system considered promising in our hunt for water on Mars.
[...]
More Information in the ALT-Text and read more on:
esa.int/Science_Exploration/Hu

CREDIT
From I. Mitrofanov et al. (2021)

ESA’s ExoMars Trace Gas Orbiter (TGO) has discovered large amounts of water locked up within Mars’ extensive canyon system, Valles Marineris. This feature is the largest canyon in the Solar System and can be seen stretching across this frame, overlaid by coloured shading representing the amount of water mixed into the uppermost metre of soil (ranging from low amounts in orange-red to high in purple-blue tones, as measured by TGO’s FREND (Fine Resolution Epithermal Neutron Detector)). The coloured scale at the bottom of the frame shows the amount of ‘water-equivalent hydrogen’ (WEH) by weight (wt%). As reflected on these scales, the purple contours in the centre of this figure show the most water-rich region. In the area marked with a ‘C’, up to 40% of the near-surface material appears to be composed of water (by weight). The area marked ‘C’ is about the size of the Netherlands and overlaps with the deep valleys of Candor Chaos, part of the canyon system considered promising in our hunt for water on Mars. The underlying grey shading in this image represents surface topography, and is based on data from the Mars Global Surveyor Mars Orbiter Laser Altimeter (MGS/MOLA). The axes around the frame show location (latitude and longitude) on Mars. CREDIT From I. Mitrofanov et al. (2021)

Alt...ESA’s ExoMars Trace Gas Orbiter (TGO) has discovered large amounts of water locked up within Mars’ extensive canyon system, Valles Marineris. This feature is the largest canyon in the Solar System and can be seen stretching across this frame, overlaid by coloured shading representing the amount of water mixed into the uppermost metre of soil (ranging from low amounts in orange-red to high in purple-blue tones, as measured by TGO’s FREND (Fine Resolution Epithermal Neutron Detector)). The coloured scale at the bottom of the frame shows the amount of ‘water-equivalent hydrogen’ (WEH) by weight (wt%). As reflected on these scales, the purple contours in the centre of this figure show the most water-rich region. In the area marked with a ‘C’, up to 40% of the near-surface material appears to be composed of water (by weight). The area marked ‘C’ is about the size of the Netherlands and overlaps with the deep valleys of Candor Chaos, part of the canyon system considered promising in our hunt for water on Mars. The underlying grey shading in this image represents surface topography, and is based on data from the Mars Global Surveyor Mars Orbiter Laser Altimeter (MGS/MOLA). The axes around the frame show location (latitude and longitude) on Mars. CREDIT From I. Mitrofanov et al. (2021)

    [?]grobi » 🌐
    @grobi@defcon.social

    Sun news: Is the low sun activity the calm before the storm?
    -- C. Alex Young

    Today’s top story: Sun flare activity dropped back to low over the past day, with only faint C-class flares. But the past day’s flare count rose in contrast to recent days. We saw 15 flares in this period versus as few as six earlier in the week. Are we seeing the calm before the storm? We observed fiery activity on the northeast limb through repeated, slow, arching prominences. This action may rotate into Earth’s view in the coming days. Could it bring a surge in solar activity? Stay tuned.
    earthsky.org/sun/sun-news-acti

    Alt...Sun news for September 25-26, 2025. Prominence activity danced over northeast limb sending chromospheric plasma up and down in the solar corona. Flare activity: Solar activity stayed at a low level, producing only C-class flares. The sun fired off 15 C-class flares during the period. + Strongest: C3.4 from AR4217 at 14:01 UTC on September 25. * Other notable events: C2.4 (AR4226 at 19:21 UTC), C2.4 (from an incoming unnumbered region in the northeast at 6:28 UTC), and C2.3 (AR4220 at 18:53 UTC). The newcomer in the northeast led the count with seven C flares, closely followed by AR4217 with five. Images via NOAA/GOES.

    As will other geostationary satellites, twice a year the spacecraft experiences an “eclipse” season where the Earth comes between the sun and the spacecraft for an approximately two week period. Images via NOAA/GOES.

    Alt...As will other geostationary satellites, twice a year the spacecraft experiences an “eclipse” season where the Earth comes between the sun and the spacecraft for an approximately two week period. Images via NOAA/GOES.

    This image shows sun activity – with the most active regions labeled – as of 4 UTC on September 27, 2025, as seen from Learmonth Solar Observatory in Australia. * Original image, without labels, via NSO/GONG. * Today’s sun is posted by Armando Caussade. Q: Why are east and west on the sun reversed? Flare activity: Solar activity stayed at a low level, producing only C-class flares. The sun fired off 15 C-class flares during the period. Strongest: C3.4 from AR4217 at 14:01 UTC on September 25. Other notable events: C2.4 (AR4226 at 19:21 UTC), C2.4 (from an incoming unnumbered region in the northeast at 6:28 UTC), and C2.3 (AR4220 at 18:53 UTC). The newcomer in the northeast led the count with seven C flares, closely followed by AR4217 with five. Sunspot regions: Ten numbered active regions covered the Earth-facing solar disk. The four regions — AR4230 (southeast), AR4217 (southwest), AR4226 (southeast), and AR4229 (southwest) — that showed gamma magnetic complexity yesterday, all simplified to beta configurations today. The rest of the regions remained small, stable, or in slow decay. A newcomer appeared in the southwest and was numbered AR4231.

    Alt...This image shows sun activity – with the most active regions labeled – as of 4 UTC on September 27, 2025, as seen from Learmonth Solar Observatory in Australia. * Original image, without labels, via NSO/GONG. * Today’s sun is posted by Armando Caussade. Q: Why are east and west on the sun reversed? Flare activity: Solar activity stayed at a low level, producing only C-class flares. The sun fired off 15 C-class flares during the period. Strongest: C3.4 from AR4217 at 14:01 UTC on September 25. Other notable events: C2.4 (AR4226 at 19:21 UTC), C2.4 (from an incoming unnumbered region in the northeast at 6:28 UTC), and C2.3 (AR4220 at 18:53 UTC). The newcomer in the northeast led the count with seven C flares, closely followed by AR4217 with five. Sunspot regions: Ten numbered active regions covered the Earth-facing solar disk. The four regions — AR4230 (southeast), AR4217 (southwest), AR4226 (southeast), and AR4229 (southwest) — that showed gamma magnetic complexity yesterday, all simplified to beta configurations today. The rest of the regions remained small, stable, or in slow decay. A newcomer appeared in the southwest and was numbered AR4231.

    An M1.6 solar flare from AR4224 captured by the SUVI instrument onboard the GOES spacecraft. Images via NOAA. Sun activity jumped up to moderate with the production of an M1.0 flare from active region AR4217 in the southwest. The blast occurred at 10:34 UTC on September 23. Along with the M flare, a type II radio emission was registered at 10:43 UTC along with an R1 (minor) radio blackout observed over Africa. Total flare production also doubled compared to the previous day, with 14 flares blasted out during the past 24 hours.

    Alt...An M1.6 solar flare from AR4224 captured by the SUVI instrument onboard the GOES spacecraft. Images via NOAA. Sun activity jumped up to moderate with the production of an M1.0 flare from active region AR4217 in the southwest. The blast occurred at 10:34 UTC on September 23. Along with the M flare, a type II radio emission was registered at 10:43 UTC along with an R1 (minor) radio blackout observed over Africa. Total flare production also doubled compared to the previous day, with 14 flares blasted out during the past 24 hours.

      [?]grobi » 🌐
      @grobi@defcon.social

      2025 June 20

      Major Lunar Standstill 2024-2025
      * Image Credit & Copyright: Luca Vanzella, Alister Ling
      flickr.com/people/53851348@N05/
      flickr.com/people/99775232@N07/

      Explanation:
      Edmonton, Alberta, Canada, planet Earth lies on the horizon. in this stack of panoramic composite images. In a monthly time series arranged vertically top to bottom the ambitious photographic project follows the annual north-south swing of sunrise points, from June solstice to December solstice and back again. It also follows the corresponding, but definitely harder to track, Full Moon rise. Of course, the north-south swing of moonrise runs opposite sunrise along the horizon. But these rising Full Moons also span a wider range on the horizon than the sunrises. That's because the well-planned project (as shown in this video !>>) covers the period June 2024 to June 2025, centered on a major lunar standstill. Major lunar standstills represent extremes in the north-south range of moonrise driven by the 18.6 year precession period of the lunar orbit.
      en.wikipedia.org/wiki/Lunar_st
      griffithobservatory.org/extrem

      earthsky.org/tonight/june-full
      !>> youtube.com/watch?v=u1tkLRdaFNk
      earthsky.org/astronomy-essenti
      apod.nasa.gov/apod/ap160922.ht

      apod.nasa.gov/apod/ap160922.ht

      2025 June 20 Major Lunar Standstill 2024-2025 * Image Credit & Copyright: Luca Vanzella, Alister Ling Explanation: Edmonton, Alberta, Canada, planet Earth lies on the horizon. in this stack of panoramic composite images. In a monthly time series arranged vertically top to bottom the ambitious photographic project follows the annual north-south swing of sunrise points, from June solstice to December solstice and back again. It also follows the corresponding, but definitely harder to track, Full Moon rise. Of course, the north-south swing of moonrise runs opposite sunrise along the horizon. But these rising Full Moons also span a wider range on the horizon than the sunrises. That's because the well-planned project (as shown in this video) covers the period June 2024 to June 2025, centered on a major lunar standstill. Major lunar standstills represent extremes in the north-south range of moonrise driven by the 18.6 year precession period of the lunar orbit. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

      Alt...2025 June 20 Major Lunar Standstill 2024-2025 * Image Credit & Copyright: Luca Vanzella, Alister Ling Explanation: Edmonton, Alberta, Canada, planet Earth lies on the horizon. in this stack of panoramic composite images. In a monthly time series arranged vertically top to bottom the ambitious photographic project follows the annual north-south swing of sunrise points, from June solstice to December solstice and back again. It also follows the corresponding, but definitely harder to track, Full Moon rise. Of course, the north-south swing of moonrise runs opposite sunrise along the horizon. But these rising Full Moons also span a wider range on the horizon than the sunrises. That's because the well-planned project (as shown in this video) covers the period June 2024 to June 2025, centered on a major lunar standstill. Major lunar standstills represent extremes in the north-south range of moonrise driven by the 18.6 year precession period of the lunar orbit. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

        [?]grobi » 🌐
        @grobi@defcon.social

        The Major Lunar Standstill - a real, visual representation
        by
        Luca Vanzella: vanzella.com/luca-vanzellas-as
        Alister Ling: astronomy.com/author/alister-l
        This video shows thirteen moonrise and thirteen sunrise images from June 2024 to June 2025, to visually depict the change in moonrise/sunrise position over a year and to illustrate that the greatest northern and southern positions of the Moon extend beyond those of the Sun during a Major Lunar Standstill (griffithobservatory.org/extre....

        Short Story

        Celebrating the northeastern and southeastern extremes of sunrise points (solstices) are familiar experiences to all casual skywatchers but the moonrise extremes (lunistices) mostly go unnoticed except to attentive observers. As the Moon’s orbit slowly regresses in an 18.6 year cycle, the span of moonrise points varies between two extremes: the minor and major lunar standstills. In a major lunar standstill, the extreme moonrise points are several degrees farther north and south than the sunrise ones. Inspired by an earlier project ( • A Year of Sunrises ) of creating a time slice of sunrises, we wanted to capture these events photographically in a manner both educationally and visually compelling.

        Technically the Major Lunar Standstill is a point in time on the dates of the extreme north and south lunar declinations, both occurring in March 2025, but similar to solstices, it is best appreciated in the context of a period of observation. Any consistent phase would reveal the pattern, but a full Moon is the most eye-catching and stands out best in very wide images.

        The period from the June 2024 solstice to thttps://defcon.social/keyboard-shortcutshe June 2025 solstice nicely surrounds the standstill, so we shot thirteen full moonrises and thirteen sunrises to represent the Major Lunar Standstill with a vertical time slice composite image and this video.

        Alt...Camera: T3i / Canon 60D Lens: Canon EF-S 10-18mm @ 10mm Settings: ISO 200, Daylight WB, f/4.5 Sunrises: 3x1EV bracket, e.g.: 1/125, 1/250, 1/500 sec Moonrises: 6x2EV bracket, e.g.: 2, 1/2, 1/8, 1/30, 1/125, 1/500 sec Event Data Here's the essential data from the 26 events. Each sunrise was planned to capture the Sun about 0.5° above the horizon, while each moonrise was planned to capture the Moon about 2.5° above the horizon. Target Moonrise Moon D | Sunrise Sun D Date Actual Az Az | Actual Az Az 2024 06 21 2024 06 21 151.2 0.0 | 2022 06 19 46.6 -0.1 2024 07 21 2024 07 21 134.5 0.0 | 2022 07 21 52.7 0.2 2024 08 19 2022 08 12 118.5 1.1 | 2022 08 19 67.2 0.2 2024 09 17 2022 09 10 101.8 2.6 | 2022 09 17 85.3 0.4 2024 10 17 2024 10 17 69.5 0.0 | 2022 10 17 104.8 0.3 2024 11 15 2023 11 26 54.8 0.1 | 2022 11 14 120.6 0.8 2024 12 15 2023 11 28 44.9 1.4 | 2022 12 13 130.0 0.3 2025 01 13 2025 01 13 49.1 0.0 | 2022 01 16 125.4 1.0 2025 02 12 2025 02 17 71.1 0.0 | 2022 02 11 112.6 -0.7 2025 03 14 2023 04 05 101.6 3.8 | 2022 03 16 91.6 1.2 2025 04 12 2025 04 12 115.7 1.0 | 2022 04 11 74.6 -0.8 2025 05 12 2022 07 13 142.7 3.0 | 2022 05 12 57.0 -0.1 2025 06 11 2024 05 25 151.0 0.0 | 2022 06 12 47.1 0.1

          [?]grobi » 🌐
          @grobi@defcon.social

          June solstice in 2025: All you need to know
          By Editors of EarthSky
          June 15, 2025

          A solstice lasts only a moment, when the sun is at its farthest north in our sky for an entire year. In 2025, the solstice moment will fall at 2:42 UTC on June 21. That’s 9:42 p.m. on June 20 for us in central North America. Yet many will celebrate this solstice for a whole day. What makes this day so special? And what is a solstice? Join EarthSky’s Deborah Byrd with a preview of the June solstice 2025. Watch in the player below.

          earthsky.org/astronomy-essenti

          Alt...June solstice in 2025: All you need to know By Editors of EarthSky June 15, 2025 A solstice lasts only a moment, when the sun is at its farthest north in our sky for an entire year. In 2025, the solstice moment will fall at 2:42 UTC on June 21. That’s 9:42 p.m. on June 20 for us in central North America. Yet many will celebrate this solstice for a whole day. What makes this day so special? And what is a solstice? Join EarthSky’s Deborah Byrd with a preview of the June solstice 2025. Watch in the player below.

            [?]grobi » 🌐
            @grobi@defcon.social

            2025 July 1
            A fisheye image of the sky is shown on the left with the landscape-foreground surrounding it. The plane of our Milky Way Galaxy runs down the center. At first glance the sky looks like oddly like an eye of a dragon.

            Eye Sky a Dragon
            * Image Credit & Copyright: Anton Komlev
            instagram.com/komlev.av/

            Explanation:
            What do you see when you look into this sky? In the center, in the dark, do you see a night sky filled with stars? Do you see a sunset to the left? Clouds all around? Do you see the central band of our Milky Way Galaxy running down the middle? Do you see the ruins of an abandoned outpost on a hill? (The outpost is on Askold Island, Russia.) Do you see a photographer with a headlamp contemplating surreal surroundings? (The featured image is a panorama of 38 images taken last month and compiled into a Little Planet projection.) Do you see a rugged path lined with steps? Or do you see the eye of a dragon?
            instagram.com/p/B1r5mYWIi9k/

            Location:
            youtube.com/watch?v=MBRMXR8y9Nc
            rbth.com/arts/travel/2013/09/2
            en.wikipedia.org/wiki/Russia

            DIY:
            photographymad.com/pages/view/

            For Your Desktop:
            getwallpapers.com/collection/d

            apod.nasa.gov/apod/ap250701.ht

            2025 July 1 A fisheye image of the sky is shown on the left with the landscape-foreground surrounding it. The plane of our Milky Way Galaxy runs down the center. At first glance the sky looks like oddly like an eye of a dragon. Eye Sky a Dragon * Image Credit & Copyright: Anton Komlev Explanation: What do you see when you look into this sky? In the center, in the dark, do you see a night sky filled with stars? Do you see a sunset to the left? Clouds all around? Do you see the central band of our Milky Way Galaxy running down the middle? Do you see the ruins of an abandoned outpost on a hill? (The outpost is on Askold Island, Russia.) Do you see a photographer with a headlamp contemplating surreal surroundings? (The featured image is a panorama of 38 images taken last month and compiled into a Little Planet projection.) Do you see a rugged path lined with steps? Or do you see the eye of a dragon? Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation

            Alt...2025 July 1 A fisheye image of the sky is shown on the left with the landscape-foreground surrounding it. The plane of our Milky Way Galaxy runs down the center. At first glance the sky looks like oddly like an eye of a dragon. Eye Sky a Dragon * Image Credit & Copyright: Anton Komlev Explanation: What do you see when you look into this sky? In the center, in the dark, do you see a night sky filled with stars? Do you see a sunset to the left? Clouds all around? Do you see the central band of our Milky Way Galaxy running down the middle? Do you see the ruins of an abandoned outpost on a hill? (The outpost is on Askold Island, Russia.) Do you see a photographer with a headlamp contemplating surreal surroundings? (The featured image is a panorama of 38 images taken last month and compiled into a Little Planet projection.) Do you see a rugged path lined with steps? Or do you see the eye of a dragon? Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation

              [?]grobi » 🌐
              @grobi@defcon.social

              2025 July 18

              ISS Meets Saturn
              * Image Credit & Copyright: A.J. Smadi
              instagram.com/aj.smadi/

              Explanation:
              This month, bright planet Saturn rises in evening skies, its rings oriented nearly edge-on when viewed from planet Earth. And in the early morning hours on July 6, it posed very briefly with the International Space Station when viewed from a location in Federal Way, Washington, USA. This well-planned image, a stack of video frames, captures their momentary conjunction in the same telescopic field of view. With the ISS in low Earth orbit, space station and gas giant planet were separated by almost 1.4 billion kilometers. Their apparent sizes are comparable but the ISS was much brighter than Saturn and the ringed planet's brightness has been increased for visibility in the stacked image. Precise timing and an exact location were needed to capture the ISS/Saturn conjunction.
              nasa.gov/spot-the-station/
              nasa.gov/missions/station/iss-
              apod.nasa.gov/apod/image/2507/

              apod.nasa.gov/apod/ap250718.ht

              Image with annotations 2025 July 18 ISS Meets Saturn * Image Credit & Copyright: A.J. Smadi Explanation: This month, bright planet Saturn rises in evening skies, its rings oriented nearly edge-on when viewed from planet Earth. And in the early morning hours on July 6, it posed very briefly with the International Space Station when viewed from a location in Federal Way, Washington, USA. This well-planned image, a stack of video frames, captures their momentary conjunction in the same telescopic field of view. With the ISS in low Earth orbit, space station and gas giant planet were separated by almost 1.4 billion kilometers. Their apparent sizes are comparable but the ISS was much brighter than Saturn and the ringed planet's brightness has been increased for visibility in the stacked image. Precise timing and an exact location were needed to capture the ISS/Saturn conjunction. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

              Alt...Image with annotations 2025 July 18 ISS Meets Saturn * Image Credit & Copyright: A.J. Smadi Explanation: This month, bright planet Saturn rises in evening skies, its rings oriented nearly edge-on when viewed from planet Earth. And in the early morning hours on July 6, it posed very briefly with the International Space Station when viewed from a location in Federal Way, Washington, USA. This well-planned image, a stack of video frames, captures their momentary conjunction in the same telescopic field of view. With the ISS in low Earth orbit, space station and gas giant planet were separated by almost 1.4 billion kilometers. Their apparent sizes are comparable but the ISS was much brighter than Saturn and the ringed planet's brightness has been increased for visibility in the stacked image. Precise timing and an exact location were needed to capture the ISS/Saturn conjunction. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

              Edited Image of ISS in front of Saturn

              Alt...Edited Image of ISS in front of Saturn

              Unedited Image of ISS in front of Saturn.

              Alt...Unedited Image of ISS in front of Saturn.

                [?]grobi » 🌐
                @grobi@defcon.social

                "Why not take to the air right away?"

                2020 February 9

                To Fly Free in Space
                * Image Credit: NASA, STS-41B
                nasa.gov/
                nasa.gov/mission/sts-41b/

                Explanation:
                What would it be like to fly free in space? At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was living the dream -- floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space. McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk" during Space Shuttle mission 41-B in 1984. The MMU worked by shooting jets of nitrogen and was used to help deploy and retrieve satellites. With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is weightless when drifting in orbit. The MMU was later replaced with the SAFER backpack propulsion unit.
                en.wikipedia.org/wiki/Manned_M

                apod.nasa.gov/apod/ap200209.ht

                2020 February 9 To Fly Free in Space * Image Credit: NASA, STS-41B Explanation: What would it be like to fly free in space? At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was living the dream -- floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space. McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk" during Space Shuttle mission 41-B in 1984. The MMU worked by shooting jets of nitrogen and was used to help deploy and retrieve satellites. With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is weightless when drifting in orbit. The MMU was later replaced with the SAFER backpack propulsion unit. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                Alt...2020 February 9 To Fly Free in Space * Image Credit: NASA, STS-41B Explanation: What would it be like to fly free in space? At about 100 meters from the cargo bay of the space shuttle Challenger, Bruce McCandless II was living the dream -- floating farther out than anyone had ever been before. Guided by a Manned Maneuvering Unit (MMU), astronaut McCandless, pictured, was floating free in space. McCandless and fellow NASA astronaut Robert Stewart were the first to experience such an "untethered space walk" during Space Shuttle mission 41-B in 1984. The MMU worked by shooting jets of nitrogen and was used to help deploy and retrieve satellites. With a mass over 140 kilograms, an MMU is heavy on Earth, but, like everything, is weightless when drifting in orbit. The MMU was later replaced with the SAFER backpack propulsion unit. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                  [?]grobi » 🌐
                  @grobi@defcon.social

                  Dawn of the Crab
                  * Image and Text Credit: Bradley E. Schaefer
                  lsu.edu/physics/people/faculty

                  Explanation:
                  One of the all-time historic skyscapes occured in July 1054, when the Crab Supernova blazed into the dawn sky. Chinese court astrologers first saw the Guest Star on the morning of 4 July 1054 next to the star Tianguan (now cataloged as Zeta Tauri). The supernova peaked in late July 1054 a bit brighter than Venus, and was visible in the daytime for 23 days. The Guest Star was so bright that every culture around the world inevitably discovered the supernova independently, although only nine reports survive, including those from China, Japan, and Constantinople. This iPhone picture is from Signal Hill near Tucson on the morning of 26 July 2025, faithfully re-creates the year 1054 Dawn of the Crab, showing the sky as seen by Hohokam peoples. The planet Venus, as a stand-in for the supernova, is close to the position of what is now the Crab Nebula supernova remnant. Step outside on a summer dawn with bright Venus, and ask yourself "What would you have thought in ancient times when suddenly seeing the Dawn of the Crab?"

                  + Crab Nebula:
                  en.wikipedia.org/wiki/SN_1054
                  apod.nasa.gov/apod/ap011227.ht
                  + Zeta Tauri:
                  star-facts.com/tianguan-zeta-t
                  stars.astro.illinois.edu/sow/z
                  + Astrophysics:
                  ui.adsabs.harvard.edu/abs/2003

                  + History:
                  ui.adsabs.harvard.edu/abs/2003
                  kyohaku.go.jp/eng/learn/home/d
                  nytimes.com/1978/07/18/archive
                  + Hystorical Chinese Astrology:
                  lehigh.edu/~dwp0/Assets/images
                  + Cultural:
                  britannica.com/topic/Hohokam-c
                  nps.gov/articles/000/signal-hi

                  + Education:
                  spaceplace.nasa.gov/supernova/

                  apod.nasa.gov/apod/ap250808.ht

                  The Dawn Sky Of 26 July 1054 AD (with annotations) 2025 August 8 Dawn of the Crab * Image and Text Credit: Bradley E. Schaefer Explanation: One of the all-time historic skyscapes occured in July 1054, when the Crab Supernova blazed into the dawn sky. Chinese court astrologers first saw the Guest Star on the morning of 4 July 1054 next to the star Tianguan (now cataloged as Zeta Tauri). The supernova peaked in late July 1054 a bit brighter than Venus, and was visible in the daytime for 23 days. The Guest Star was so bright that every culture around the world inevitably discovered the supernova independently, although only nine reports survive, including those from China, Japan, and Constantinople. This iPhone picture is from Signal Hill near Tucson on the morning of 26 July 2025, faithfully re-creates the year 1054 Dawn of the Crab, showing the sky as seen by Hohokam peoples. The planet Venus, as a stand-in for the supernova, is close to the position of what is now the Crab Nebula supernova remnant. Step outside on a summer dawn with bright Venus, and ask yourself "What would you have thought in ancient times when suddenly seeing the Dawn of the Crab?" Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                  Alt...The Dawn Sky Of 26 July 1054 AD (with annotations) 2025 August 8 Dawn of the Crab * Image and Text Credit: Bradley E. Schaefer Explanation: One of the all-time historic skyscapes occured in July 1054, when the Crab Supernova blazed into the dawn sky. Chinese court astrologers first saw the Guest Star on the morning of 4 July 1054 next to the star Tianguan (now cataloged as Zeta Tauri). The supernova peaked in late July 1054 a bit brighter than Venus, and was visible in the daytime for 23 days. The Guest Star was so bright that every culture around the world inevitably discovered the supernova independently, although only nine reports survive, including those from China, Japan, and Constantinople. This iPhone picture is from Signal Hill near Tucson on the morning of 26 July 2025, faithfully re-creates the year 1054 Dawn of the Crab, showing the sky as seen by Hohokam peoples. The planet Venus, as a stand-in for the supernova, is close to the position of what is now the Crab Nebula supernova remnant. Step outside on a summer dawn with bright Venus, and ask yourself "What would you have thought in ancient times when suddenly seeing the Dawn of the Crab?" Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                  The Dawn Sky Of 26 July 2025 AD (with annotations)

                  Alt...The Dawn Sky Of 26 July 2025 AD (with annotations)

                    [?]grobi » 🌐
                    @grobi@defcon.social

                    2025 September 26

                    A SWAN, an ATLAS, and Mars
                    * Image Credit & Copyright: Adam Block
                    adamblockphotos.com/

                    Explanation:
                    A new visitor to the inner Solar System, comet C/2025 R2 (SWAN) sports a long ion tail extending diagonally across this almost 7 degree wide telescopic field of view recorded on September 21. A fainter fellow comet also making its inner Solar System debut, C/2025 K1 (ATLAS), can be spotted above and left of SWAN's greenish coma, just visible against the background sea of stars in the constellation Virgo. Both new comets were only discovered in 2025 and are joined in this celestial frame by ruddy planet Mars (bottom), a more familiar wanderer in planet Earth's night skies. The comets may appear to be in a race, nearly neck and neck in their voyage through the inner Solar System and around the Sun. But this comet SWAN has already reached its perihelion or closest approach to the Sun on September 12 and is now outbound along its orbit. This comet ATLAS is still inbound though, and will make its perihelion passage on October 8.
                    app.astrobin.com/i/vf43w6
                    skyatnightmagazine.com/news/c-
                    theskylive.com/c2025k1-info
                    theskylive.com/c2025k1-info

                    apod.nasa.gov/apod/ap250926.ht

                    2025 September 26 A SWAN, an ATLAS, and Mars * Image Credit & Copyright: Adam Block Explanation: A new visitor to the inner Solar System, comet C/2025 R2 (SWAN) sports a long ion tail extending diagonally across this almost 7 degree wide telescopic field of view recorded on September 21. A fainter fellow comet also making its inner Solar System debut, C/2025 K1 (ATLAS), can be spotted above and left of SWAN's greenish coma, just visible against the background sea of stars in the constellation Virgo. Both new comets were only discovered in 2025 and are joined in this celestial frame by ruddy planet Mars (bottom), a more familiar wanderer in planet Earth's night skies. The comets may appear to be in a race, nearly neck and neck in their voyage through the inner Solar System and around the Sun. But this comet SWAN has already reached its perihelion or closest approach to the Sun on September 12 and is now outbound along its orbit. This comet ATLAS is still inbound though, and will make its perihelion passage on October 8. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                    Alt...2025 September 26 A SWAN, an ATLAS, and Mars * Image Credit & Copyright: Adam Block Explanation: A new visitor to the inner Solar System, comet C/2025 R2 (SWAN) sports a long ion tail extending diagonally across this almost 7 degree wide telescopic field of view recorded on September 21. A fainter fellow comet also making its inner Solar System debut, C/2025 K1 (ATLAS), can be spotted above and left of SWAN's greenish coma, just visible against the background sea of stars in the constellation Virgo. Both new comets were only discovered in 2025 and are joined in this celestial frame by ruddy planet Mars (bottom), a more familiar wanderer in planet Earth's night skies. The comets may appear to be in a race, nearly neck and neck in their voyage through the inner Solar System and around the Sun. But this comet SWAN has already reached its perihelion or closest approach to the Sun on September 12 and is now outbound along its orbit. This comet ATLAS is still inbound though, and will make its perihelion passage on October 8. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                      [?]grobi » 🌐
                      @grobi@defcon.social

                      Annotations for previous post.

                      Annotations for previous post.

                      Alt...Annotations for previous post.

                        [?]grobi » 🌐
                        @grobi@defcon.social

                        2025 September 25

                        Saturn Opposite the Sun
                        * Image Credit & Copyright: Jin Wang

                        Explanation:
                        This year Saturn was at opposition on September 21, opposite the Sun in planet Earth's sky. At its closest to Earth, Saturn was also at its brightest of the year, rising as the Sun set and shining above the horizon all night long among the fainter stars of the constellation Pisces. In this snapshot from the Qinghai Lenghu Observatory, Tibetan Plateau, southwestern China, the outer planet is immersed in a faint, diffuse oval of light known as the gegenschein or counter glow. The diffuse gegenschein is produced by sunlight backscattered by interplanetary dust along the Solar System's ecliptic plane, opposite the Sun in planet Earth's sky. Like a giant eye, on this dark night Saturn and gegenschein seem to stare down on the observatory's telescope domes seen against a colorful background of airglow along the horizon.

                        science.nasa.gov/solar-system/
                        apod.nasa.gov/apod/ap080507.ht
                        en.wikipedia.org/wiki/Wide_Fie

                        apod.nasa.gov/apod/ap250925.ht

                        2025 September 25 Saturn Opposite the Sun * Image Credit & Copyright: Jin Wang Explanation: This year Saturn was at opposition on September 21, opposite the Sun in planet Earth's sky. At its closest to Earth, Saturn was also at its brightest of the year, rising as the Sun set and shining above the horizon all night long among the fainter stars of the constellation Pisces. In this snapshot from the Qinghai Lenghu Observatory, Tibetan Plateau, southwestern China, the outer planet is immersed in a faint, diffuse oval of light known as the gegenschein or counter glow. The diffuse gegenschein is produced by sunlight backscattered by interplanetary dust along the Solar System's ecliptic plane, opposite the Sun in planet Earth's sky. Like a giant eye, on this dark night Saturn and gegenschein seem to stare down on the observatory's telescope domes seen against a colorful background of airglow along the horizon. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                        Alt...2025 September 25 Saturn Opposite the Sun * Image Credit & Copyright: Jin Wang Explanation: This year Saturn was at opposition on September 21, opposite the Sun in planet Earth's sky. At its closest to Earth, Saturn was also at its brightest of the year, rising as the Sun set and shining above the horizon all night long among the fainter stars of the constellation Pisces. In this snapshot from the Qinghai Lenghu Observatory, Tibetan Plateau, southwestern China, the outer planet is immersed in a faint, diffuse oval of light known as the gegenschein or counter glow. The diffuse gegenschein is produced by sunlight backscattered by interplanetary dust along the Solar System's ecliptic plane, opposite the Sun in planet Earth's sky. Like a giant eye, on this dark night Saturn and gegenschein seem to stare down on the observatory's telescope domes seen against a colorful background of airglow along the horizon. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                          [?]grobi » 🌐
                          @grobi@defcon.social

                          2025 September 24

                          GW250114: Rotating Black Holes Collide
                          * Illustration Credit: Aurore Simonnet (SSU/EdEon), LVK, URI; LIGO Collaboration
                          auroresimonnet.com/about-me/
                          phys-astro.sonoma.edu/
                          edeon.sonoma.edu/
                          ligo.caltech.edu/page/ligo-sci

                          Explanation:
                          It was the strongest gravitational wave signal yet measured -- what did it show? GW250114 was detected by both arms of the Laser Interferometer Gravitational-wave Observatory (LIGO) in Washington and Louisiana USA earlier this year. Analysis showed that the event was created when two black holes, each of mass around 33 times the mass of the Sun, coalesced into one larger black hole with a mass of around 63 solar masses. Even though the event happened about a billion light years away, the signal was so strong that the spin of all black holes, as well as initial ringing of the final black hole, was deduced with exceptional accuracy. Furthermore, it was confirmed better than before, as previously predicted, that the total event horizon area of the combined black hole was greater than those of the merging black holes. Featured, an artist's illustration depicts an imaginative and conceptual view from near one of the black holes before collision.
                          ligo.caltech.edu/
                          caltech.edu/about/news/first-o
                          science.nasa.gov/universe/blac
                          apod.nasa.gov/apod/ap190414.ht
                          apod.nasa.gov/htmltest/rjn_bht

                          spaceplace.nasa.gov/black-hole
                          apod.nasa.gov/apod/ap191001.ht
                          en.wikipedia.org/wiki/Black_ho
                          en.wikipedia.org/wiki/GW250114

                          apod.nasa.gov/apod/ap250924.ht

                          2025 September 24 Artwork depicts a colorful version of two black holes nearing collision from between the black holes. Swirling gas is depicted with wavey lined depicting gravitational waves ringing and an artificial grid depicting spacetime shown distorting. GW250114: Rotating Black Holes Collide * Illustration Credit: Aurore Simonnet (SSU/EdEon), LVK, URI; LIGO Collaboration Explanation: It was the strongest gravitational wave signal yet measured -- what did it show? GW250114 was detected by both arms of the Laser Interferometer Gravitational-wave Observatory (LIGO) in Washington and Louisiana USA earlier this year. Analysis showed that the event was created when two black holes, each of mass around 33 times the mass of the Sun, coalesced into one larger black hole with a mass of around 63 solar masses. Even though the event happened about a billion light years away, the signal was so strong that the spin of all black holes, as well as initial ringing of the final black hole, was deduced with exceptional accuracy. Furthermore, it was confirmed better than before, as previously predicted, that the total event horizon area of the combined black hole was greater than those of the merging black holes. Featured, an artist's illustration depicts an imaginative and conceptual view from near one of the black holes before collision. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply.

                          Alt...2025 September 24 Artwork depicts a colorful version of two black holes nearing collision from between the black holes. Swirling gas is depicted with wavey lined depicting gravitational waves ringing and an artificial grid depicting spacetime shown distorting. GW250114: Rotating Black Holes Collide * Illustration Credit: Aurore Simonnet (SSU/EdEon), LVK, URI; LIGO Collaboration Explanation: It was the strongest gravitational wave signal yet measured -- what did it show? GW250114 was detected by both arms of the Laser Interferometer Gravitational-wave Observatory (LIGO) in Washington and Louisiana USA earlier this year. Analysis showed that the event was created when two black holes, each of mass around 33 times the mass of the Sun, coalesced into one larger black hole with a mass of around 63 solar masses. Even though the event happened about a billion light years away, the signal was so strong that the spin of all black holes, as well as initial ringing of the final black hole, was deduced with exceptional accuracy. Furthermore, it was confirmed better than before, as previously predicted, that the total event horizon area of the combined black hole was greater than those of the merging black holes. Featured, an artist's illustration depicts an imaginative and conceptual view from near one of the black holes before collision. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply.

                            [?]grobi » 🌐
                            @grobi@defcon.social

                            TOPIC >
                            Supermassive Black Holes

                            Spin up of a Supermassive Black Hole
                            * Illustration Credit: Robert Hurt, NASA/JPL-Caltech
                            ipac.caltech.edu/science/staff
                            jpl.nasa.gov/
                            nasa.gov/

                            Explanation:
                            How fast can a black hole spin? If any object made of regular matter spins too fast -- it breaks apart. But a black hole might not be able to break apart -- and its maximum spin rate is really unknown. Theorists usually model rapidly rotating black holes with the Kerr solution to Einstein's General Theory of Relativity, which predicts several amazing and unusual things. Perhaps its most easily testable prediction, though, is that matter entering a maximally rotating black hole should be last seen orbiting at near the speed of light, as seen from far away. This prediction was tested by NASA's NuSTAR and ESA's XMM satellites by observing the supermassive black hole at the center of spiral galaxy NGC 1365. The near light-speed limit was confirmed by measuring the heating and spectral line broadening of nuclear emissions at the inner edge of the surrounding accretion disk. Pictured here is an artist's illustration depicting an accretion disk of normal matter swirling around a black hole, with a jet emanating from the top. Since matter randomly falling into the black hole should not spin up a black hole this much, the NuSTAR and XMM measurements also validate the existence of the surrounding accretion disk.
                            jpl.nasa.gov/images/pia16695-b
                            slate.com/technology/2013/02/s
                            ui.adsabs.harvard.edu/abs/2013

                            science.nasa.gov/universe/blac
                            apod.nasa.gov/apod/ap080811.ht
                            apod.nasa.gov/htmltest/rjn_bht
                            apod.nasa.gov/apod/ap140323.ht
                            apod.nasa.gov/apod/ap241113.ht

                            apod.nasa.gov/apod/ap250504.ht

                            2025 May 4 An artistic illustration of a black hole is shown. The black spot in the center is the black hole, while the accretion disk of gas surrounding it is shown in orange. Stars and the darkness of space is shown near the top in the background. Please see the explanation for more detailed information. Spin up of a Supermassive Black Hole * Illustration Credit: Robert Hurt, NASA/JPL-Caltech Explanation: How fast can a black hole spin? If any object made of regular matter spins too fast -- it breaks apart. But a black hole might not be able to break apart -- and its maximum spin rate is really unknown. Theorists usually model rapidly rotating black holes with the Kerr solution to Einstein's General Theory of Relativity, which predicts several amazing and unusual things. Perhaps its most easily testable prediction, though, is that matter entering a maximally rotating black hole should be last seen orbiting at near the speed of light, as seen from far away. This prediction was tested by NASA's NuSTAR and ESA's XMM satellites by observing the supermassive black hole at the center of spiral galaxy NGC 1365. ... Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                            Alt...2025 May 4 An artistic illustration of a black hole is shown. The black spot in the center is the black hole, while the accretion disk of gas surrounding it is shown in orange. Stars and the darkness of space is shown near the top in the background. Please see the explanation for more detailed information. Spin up of a Supermassive Black Hole * Illustration Credit: Robert Hurt, NASA/JPL-Caltech Explanation: How fast can a black hole spin? If any object made of regular matter spins too fast -- it breaks apart. But a black hole might not be able to break apart -- and its maximum spin rate is really unknown. Theorists usually model rapidly rotating black holes with the Kerr solution to Einstein's General Theory of Relativity, which predicts several amazing and unusual things. Perhaps its most easily testable prediction, though, is that matter entering a maximally rotating black hole should be last seen orbiting at near the speed of light, as seen from far away. This prediction was tested by NASA's NuSTAR and ESA's XMM satellites by observing the supermassive black hole at the center of spiral galaxy NGC 1365. ... Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                              [?]grobi » 🌐
                              @grobi@defcon.social

                              What Is a Black Hole?

                              The Short Answer:
                              A black hole is an area of such immense gravity that nothing -- not even light -- can escape from it.

                              spaceplace.nasa.gov/black-hole

                              Alt...converted and compressed video version explaining black holes for young students

                                [?]grobi » 🌐
                                @grobi@defcon.social

                                Download a poster of this animation from NASA Space Place:

                                8.5 x 11 inches:
                                spaceplace.nasa.gov/black-hole

                                8.5 x 13 inches
                                spaceplace.nasa.gov/black-hole

                                11 x 17 inches
                                spaceplace.nasa.gov/black-hole

                                spaceplace.nasa.gov/black-hole

                                you might also like:
                                jpl.nasa.gov/edu/resources/tea

                                Image of tutorial poster for schools explaining black holes click links to download from NASA SpacePlace web page above

                                Alt...Image of tutorial poster for schools explaining black holes click links to download from NASA SpacePlace web page above

                                  [?]grobi » 🌐
                                  @grobi@defcon.social

                                  The Spinning Black Hole

                                  "Black holes are macroscopic objects with masses varying from a few solar masses to millions of solar masses.To the extent they may be considered as stationary and isolated, to that extent, they are all, every single one of them, described exactly by the Kerr solution.
                                  This is the only instance we have of an exact description of a macroscopic object.

                                  Macroscopic objects, as we see them all around us, are governed by a variety of forces, derived from a variety of approximations to a variety of physical theories.

                                  In contrast, the only elements in the construction of black holes are our basic concepts of space and time.
                                  They are, thus, almost by definition, the most perfect macroscopic objects there are in the universe. And since the general theory of relativity provides a single unique two-parameter family of solutions for their description, they are the simplest objects as well."
                                  —S. Chandrasekhar

                                  Images below explained from left to right downwards:

                                  1. Black holes are tremendous objects whose immense gravity can distort and twist space-time, the fabric that shapes our universe.

                                  2. Scientists measure the spin rates of supermassive black holes by spreading the X-ray light into different colors.

                                  3. This image taken by the ultraviolet-light monitoring camera on the European Space Agency's (ESA's) XMM-Newton telescope shows the beautiful spiral arms of the galaxy NGC1365.

                                  4. NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, has helped to show, for the first time, that the spin rates of black holes can be measured conclusively.

                                  Credit: NASA/JPL-Caltech/ESA/CfA/INAF

                                  jpl.nasa.gov/news/nasas-nustar

                                  * You may want to download and study this scientific elaboration:

                                  PROJECT F
                                  The Spinning Black Hole
                                  eftaylor.com/pub/SpinNEW.pdf

                                  1. Black holes are tremendous objects whose immense gravity can distort and twist space-time, the fabric that shapes our universe. Credit: NASA/JPL-Caltech

                                  Alt...1. Black holes are tremendous objects whose immense gravity can distort and twist space-time, the fabric that shapes our universe. Credit: NASA/JPL-Caltech

                                  2. Scientists measure the spin rates of supermassive black holes by spreading the X-ray light into different colors. Credit: NASA/JPL-Caltech

                                  Alt...2. Scientists measure the spin rates of supermassive black holes by spreading the X-ray light into different colors. Credit: NASA/JPL-Caltech

                                  3. This image taken by the ultraviolet-light monitoring camera on the European Space Agency's (ESA's) XMM-Newton telescope shows the beautiful spiral arms of the galaxy NGC1365. Credit: ESA

                                  Alt...3. This image taken by the ultraviolet-light monitoring camera on the European Space Agency's (ESA's) XMM-Newton telescope shows the beautiful spiral arms of the galaxy NGC1365. Credit: ESA

                                  4. NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, has helped to show, for the first time, that the spin rates of black holes can be measured conclusively. Credit: NASA/JPL-Caltech/ESA/CfA/INAF

                                  Alt...4. NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, has helped to show, for the first time, that the spin rates of black holes can be measured conclusively. Credit: NASA/JPL-Caltech/ESA/CfA/INAF

                                    [?]grobi » 🌐
                                    @grobi@defcon.social

                                    Journey of an observer falling inside a(n ideal) Kerr black hole and emerging in a parallel universe. (The black hole has a mass of roughly one million solar masses (Schwarzschild radius = 10 light seconds) and an angular momentum at 80% of maximality (a/M=0.8). The observer has an energy of 1.2 times its mass and zero angular momentum along the black hole's axis.)

                                    The upper left quadrant is the observer's front view (for a somewhat arbitrary definition of "front"), the upper right quadrant is their rear view. The lower left quadrant displays the trajectory on a polar plane cut (external horizon is red, internal horizon is green, static limit is dashed and is not seen in the video, cut discontinuity is purple, and trajectory is blue) and in a Penrose diagram (outer (I) blocks are shown in blue, inner (III) blocks are shown in pink, and intermediate (II) blocks are shown in light or dark grey according as they are white hole or black hole regions; the trajectory is again shown in blue). The bottom right quadrant shows the Boyer-Lindquist coordinates and their derivative with respect to the proper time (s) of the observer.

                                    In the video, a blue sphere is placed outside the black hole at some distance, a purple sphere is placed in negative space (i.e., beyond the singularity cut), and the outer and inner horizons are various shades of red and green in the same color scheme as in the Penrose diagram (lighter shades are white hole horizons, darker shades are black hole horizons). All spheres are checkered in an identical way, with twenty-four longitudinal stripes and twelve latitudinal (or polar) stripes, consistent with the black hole's axis. (The longitudinal stripes on the horizons rotate with the black hole.) The ring singularity itself is not visible as such, but appears as the edge rim of the purple region.

                                    *Video and Text Credits:
                                    David Madore

                                    Alt...* converted and compressed video version Notes by David Madore: Note 1: This is a mathematical abstraction: while the parameters (mass and angular momentum) for this black hole are typical for certain real black holes (namely those found in galactic nuclei), physical black holes are not thought to possess any "white hole" component, at least in the past region: so a physical black hole would appear, well, black, and there wouldn't be much of interest to see (and what happens beyond the inner horizon in a physical black hole is pretty much unknown). Note 2: A previous version of this video was already posted on YouTube ( • Visiting a Kerr black hole (old versi... ). This one differs from the previous one in that the grids on the horizons are shown to rotate with the black hole (which is reasonable for a rotating black hole), and also in that the value of the Boyer-Lindquist t coordinate has been fixed. * Credit David Madore

                                      [?]grobi » 🌐
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                                      XMM-Newton catches giant black hole’s X-ray oscillations

                                      The European Space Agency's XMM-Newton has detected rapidly fluctuating X-rays coming from the very edge of a supermassive black hole in the heart of a nearby galaxy. The results paint a fascinating picture that defies how we thought matter falls into such black holes, and points to a potential source of gravitational waves that ESA’s future mission, LISA, could see.

                                      XMM-Newton is showing us that black holes devour matter in more complex ways than astronomers first thought. Black holes are predictions of Albert Einstein’s theory of general relativity. They are gravitational monsters that imprison any piece of matter or energy that crosses their ‘surface’, a region of spacetime known as the event horizon.

                                      During its final descent into the black hole, a process known as accretion, the doomed matter forms a disc around the black hole. The gas in the accretion disc heats up and gives off mostly ultraviolet (UV) light.

                                      The UV rays interact with a cloud of electrically charged gas, or plasma, that surrounds the black hole and accretion disc. This cloud is known as the corona and the interactions give the UV rays energy, boosting them up to X-rays, which XMM-Newton can capture.

                                      XMM-Newton has been observing the supermassive black hole 1ES 1927+654 since 2011. Back then, everything was pretty normal. But in 2018, things changed.

                                      1ES 1927+654 suffered a large outburst that appeared to disrupt its surroundings because the X-ray corona disappeared. Gradually, the corona returned, and by early 2021 normality appeared to have been restored.

                                      esa.int/Science_Exploration/Sp

                                      >> there is more >>
                                      esa.int/Science_Exploration/Sp

                                      Credits:
                                      Discovery of extreme Quasi-Periodic Eruptions in a newly accreting massive black hole by L. Hernandez-García et al. is published today in Nature Astronomy. DOI 10.1038/s41550-025-02523-9


                                      Giant black hole gobbling up doomed white dwarf star XMM-Newton is showing us that black holes devour Notes for editors Discovery of extreme Quasi-Periodic Eruptions in a newly accreting massive black hole by L. Hernandez-García et al. is published today in Nature Astronomy. DOI 10.1038/s41550-025-02523-9 Dr Lorena Hernandez-Garcia is also a researcher at the Millennium Institute of Astrophysics and Millennium Nucleus TITANS, Chile. SDSS1335+0728: The awakening of a ∼106 M⊙ black hole by P. Sánchez-Sáez et al. was published in the August 2024 edition of Astronomy & Astrophysics. Contact: ESA Media relations media@esa.int

                                      Alt...Giant black hole gobbling up doomed white dwarf star XMM-Newton is showing us that black holes devour Notes for editors Discovery of extreme Quasi-Periodic Eruptions in a newly accreting massive black hole by L. Hernandez-García et al. is published today in Nature Astronomy. DOI 10.1038/s41550-025-02523-9 Dr Lorena Hernandez-Garcia is also a researcher at the Millennium Institute of Astrophysics and Millennium Nucleus TITANS, Chile. SDSS1335+0728: The awakening of a ∼106 M⊙ black hole by P. Sánchez-Sáez et al. was published in the August 2024 edition of Astronomy & Astrophysics. Contact: ESA Media relations media@esa.int

                                        [?]grobi » 🌐
                                        @grobi@defcon.social

                                        Black Hole Tidal Disruption Event

                                        When a star wanders too close to a black hole, the intense gravity will stretch the star out until it becomes a long river of hot gas, as shown in this animation. The gas is then whipped around the black hole and is gradually pulled into orbit, forming a bright disk.

                                        nustar.caltech.edu/

                                        * Credit: Science Communication Lab/DESY

                                        Alt...*converted and compressed video version: Black Hole Tidal Disruption Event When a star wanders too close to a black hole, the intense gravity will stretch the star out until it becomes a long river of hot gas, as shown in this animation. The gas is then whipped around the black hole and is gradually pulled into orbit, forming a bright disk. * Credit: Science Communication Lab/DESY

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                                          @grobi@defcon.social

                                          General_relativity

                                          General relativity, also known as the general theory of relativity, and as Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. General relativity generalizes special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time, or four-dimensional spacetime. In particular, the curvature of spacetime is directly related to the energy and momentum of whatever is present, including matter and radiation. The relation is specified by the Einstein field equations, a system of second-order partial differential equations.

                                          Newton's law of universal gravitation, which describes classical gravity, can be seen as a prediction of general relativity for the almost flat spacetime geometry around stationary mass distributions. Some predictions of general relativity, however, are beyond Newton's law of universal gravitation in classical physics. These predictions concern the passage of time, the geometry of space, the motion of bodies in free fall, and the propagation of light, and include gravitational time dilation, gravitational lensing, the gravitational redshift of light, the Shapiro time delay and singularities/black holes. So far, all tests of general relativity have been shown to be in agreement with the theory. The time-dependent solutions of general relativity enable us to talk about the history of the universe and have provided the modern framework for cosmology, thus leading to the discovery of the Big Bang and cosmic microwave background radiation. ..
                                          >> en.wikipedia.org/wiki/General_

                                          * relatively related:
                                          en.wikipedia.org/wiki/Kerr_met
                                          en.wikipedia.org/wiki/Penrose_
                                          physicsopenlab.org/2017/09/07/

                                          * Credits: Wikimedia Commons

                                          Alt...Slow motion computer simulation of the black hole binary system GW150914 as seen by a nearby observer, during 0.33 s of its final inspiral, merge, and ringdown. The star field behind the black holes is being heavily distorted and appears to rotate and move, due to extreme gravitational lensing, as spacetime itself is distorted and dragged around by the rotating black holes.

                                            [?]grobi » 🌐
                                            @grobi@defcon.social

                                            The Doubly Warped World of Binary Black Holes
                                            * Scientific Visualization Credit: NASA, GSFC, Jeremy Schnittman & Brian P. Powell; Text: Francis J. Reddy
                                            sedvme.gsfc.nasa.gov/sci/bio/f
                                            science.gsfc.nasa.gov/sci/bio/
                                            science.gsfc.nasa.gov/sci/bio/
                                            nasa.gov/goddard/
                                            nasa.gov/

                                            Explanation:
                                            If one black hole looks strange, what about two? Light rays from accretion disks around a pair of orbiting supermassive black holes make their way through the warped space-time produced by extreme gravity in this detailed computer visualization. The simulated accretion disks have been given different false color schemes, red for the disk surrounding a 200-million-solar-mass black hole, and blue for the disk surrounding a 100-million-solar-mass black hole. For these masses, though, both accretion disks would actually emit most of their light in the ultraviolet. The video allows us to see both sides of each black hole at the same time. Red and blue light originating from both black holes can be seen in the innermost ring of light, called the photon sphere, near their event horizons. In the past decade, gravitational waves from black hole collisions have actually been detected, although the coalescence of supermassive black holes remains undiscovered.
                                            nasa.gov/universe/new-nasa-vis
                                            apod.nasa.gov/apod/ap200825.ht
                                            en.wikipedia.org/wiki/Accretio
                                            apod.nasa.gov/apod/ap190411.ht
                                            svs.gsfc.nasa.gov/14132/
                                            ui.adsabs.harvard.edu/abs/1993
                                            apod.nasa.gov/htmltest/rjn_bht
                                            en.wikipedia.org/wiki/Photon_s
                                            apod.nasa.gov/apod/ap201104.ht

                                            apod.nasa.gov/apod/ap250506.ht

                                            Alt... 2025 May 6 The Doubly Warped World of Binary Black Holes * Scientific Visualization Credit: NASA, GSFC, Jeremy Schnittman & Brian P. Powell; Text: Francis J. Reddy Explanation: If one black hole looks strange, what about two? Light rays from accretion disks around a pair of orbiting supermassive black holes make their way through the warped space-time produced by extreme gravity in this detailed computer visualization. The simulated accretion disks have been given different false color schemes, red for the disk surrounding a 200-million-solar-mass black hole, and blue for the disk surrounding a 100-million-solar-mass black hole. For these masses, though, both accretion disks would actually emit most of their light in the ultraviolet. The video allows us to see both sides of each black hole at the same time. Red and blue light originating from both black holes can be seen in the innermost ring of light, called the photon sphere, near their event horizons. In the past decade, gravitational waves from black hole collisions have actually been detected, although the coalescence of supermassive black holes remains undiscovered Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation.

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                                              @grobi@defcon.social

                                              Black Hole Accretion Disk Visualization

                                              Credit: NASA’s Goddard Space Flight Center
                                              Jeremy Schnittman (NASA/GSFC)
                                              Scott Wiessinger (USRA)
                                              Francis Reddy (University of Maryland College Park)
                                              Francis Reddy (University of Maryland College Park)

                                              This new visualization of a black hole illustrates how its gravity distorts our view, warping its surroundings as if seen in a carnival mirror. The visualization simulates the appearance of a black hole where infalling matter has collected into a thin, hot structure called an accretion disk. The black hole’s extreme gravity skews light emitted by different regions of the disk, producing the misshapen appearance.

                                              Bright knots constantly form and dissipate in the disk as magnetic fields wind and twist through the churning gas. Nearest the black hole, the gas orbits at close to the speed of light, while the outer portions spin a bit more slowly. This difference stretches and shears the bright knots, producing light and dark lanes in the disk.

                                              Viewed from the side, the disk looks brighter on the left than it does on the right. Glowing gas on the left side of the disk moves toward us so fast that the effects of Einstein’s relativity give it a boost in brightness; the opposite happens on the right side, where gas moving away us becomes slightly dimmer. This asymmetry disappears when we see the disk exactly face on because, from that perspective, none of the material is moving along our line of sight.

                                              Closest to the black hole, the gravitational light-bending becomes so excessive that we can see the underside of the disk as a bright ring of light seemingly outlining the black hole. This so-called “photon ring” is composed of multiple rings, which grow progressively fainter and thinner, from light that has circled the black hole two, three, or even more times before escaping to reach our eyes. ...

                                              >> svs.gsfc.nasa.gov/13326

                                              Alt... * converted and compressed video version This movie shows the black hole visualization using a partial rotation, plus a long sequence where the black hole is viewed nearly edge on. The thumbnail of this video highlights and explains various aspects of the black hole visualization. This visualization is “mass invariant,” which means it can represent a black hole of any mass. The size of the black hole's shadow is proportional to its mass, but so is the size of the accreetion disk, so its properties scale accordingly. Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

                                                [?]grobi » 🌐
                                                @grobi@defcon.social

                                                The black hole’s extreme gravitational field redirects and distorts light coming from different parts of the disk, but exactly what we see depends on our viewing angle. The greatest distortion occurs when viewing the system nearly edgewise.

                                                As our viewpoint rotates around the black hole, we see different parts of the fast-moving gas in the accretion disk moving directly toward us. Due to a phenomenon called "relativistic Doppler beaming," gas in the disk that's moving toward us makes that side of the disk appear brighter, the opposite side darker. This effect disappears when we're directly above or below the disk because, from that angle, none of the gas is moving directly toward us.

                                                When our viewpoint passes beneath the disk, it looks like the gas is moving in the opposite direction. This is no different that viewing a clock from behind, which would make it look like the hands are moving counter-clockwise.

                                                CORRECTION: In earlier versions of the 360-degree movies on this page, these important effects were not apparent. This was due to a minor mistake in orienting the camera relative to the disk. The fact that it was not initially discovered by the NASA scientist who made the movie reflects just how bizarre and counter-intuitive black holes can be!

                                                Credit: NASA’s Goddard Space Flight Center
                                                Jeremy Schnittman (NASA/GSFC)
                                                Scott Wiessinger (USRA)
                                                Francis Reddy (University of Maryland College Park)
                                                Francis Reddy (University of Maryland College Park)

                                                >>svs.gsfc.nasa.gov/13326#sectio

                                                This image highlights and explains various aspects of the black hole visualization. Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

                                                Alt...This image highlights and explains various aspects of the black hole visualization. Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

                                                This illustration shows how direct and bent light rays from a black hole's accretion disk produce the apparent image and motion seen by an observer. Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

                                                Alt...This illustration shows how direct and bent light rays from a black hole's accretion disk produce the apparent image and motion seen by an observer. Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

                                                Alt...360-degree rotation and a pause when the view is almost edge on; uses a square frame to show the complete accretion disk. Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

                                                Alt...Zoomed into the central region, highlighting the photon ring, with 360-degree rotation and a pause at almost edge on. Credit: NASA’s Goddard Space Flight Center/Jeremy Schnittman

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                                                  @grobi@defcon.social

                                                  IXPE Explores a Black Hole Jet
                                                  Illustration Credit: NASA, Pablo Garcia
                                                  nasa.gov/

                                                  Explanation:
                                                  How do black holes create X-rays? Answering this long-standing question was significantly advanced recently with data taken by NASA’s IXPE satellite. X-rays cannot exit a black hole, but they can be created in the energetic environment nearby, in particular by a jet of particles moving outward. By observing X-ray light arriving from near the supermassive black hole at the center of galaxy BL Lac, called a blazar, it was discovered that these X-rays lacked significant polarization, which is expected when created more by energetic electrons than protons. In the featured artistic illustration, a powerful jet is depicted emanating from an orange-colored accretion disk circling the black hole. Understanding highly energetic processes across the universe helps humanity to understand similar processes that occur on or near our Earth.
                                                  nasa.gov/missions/ixpe/nasas-i
                                                  apod.nasa.gov/apod/ap031128.ht
                                                  apod.nasa.gov/apod/ap240507.ht
                                                  apod.nasa.gov/apod/ap250504.ht
                                                  en.wikipedia.org/wiki/Blazar
                                                  en.wikipedia.org/wiki/Polariza

                                                  en.wikipedia.org/wiki/BL_Lacer

                                                  home.cern/science/physics
                                                  ui.adsabs.harvard.edu/abs/2025
                                                  science.nasa.gov/ems/11_xrays/
                                                  pwg.gsfc.nasa.gov/Education/wh
                                                  home.cern/news/news/physics/pr
                                                  chandra.si.edu/art/xray/

                                                  spaceplace.nasa.gov/aurora/en/

                                                  apod.nasa.gov/apod/ap250509.ht

                                                  2025 May 9 An artist's illustration of what the surroundings of the supermassive black hole at the center of BL Lac is shown. A white jet protrudes horizontally toward the bottom of the image, emanating from a orange accretion disk surrounding a black hole. Please see the explanation for more detailed information. IXPE Explores a Black Hole Jet Illustration Credit: NASA, Pablo Garcia Explanation: How do black holes create X-rays? Answering this long-standing question was significantly advanced recently with data taken by NASA’s IXPE satellite. X-rays cannot exit a black hole, but they can be created in the energetic environment nearby, in particular by a jet of particles moving outward. By observing X-ray light arriving from near the supermassive black hole at the center of galaxy BL Lac, called a blazar, it was discovered that these X-rays lacked significant polarization, which is expected when created more by energetic electrons than protons. In the featured artistic illustration, a powerful jet is depicted emanating from an orange-colored accretion disk circling the black hole. Understanding highly energetic processes across the universe helps humanity to understand similar processes that occur on or near our Earth. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                                                  Alt...2025 May 9 An artist's illustration of what the surroundings of the supermassive black hole at the center of BL Lac is shown. A white jet protrudes horizontally toward the bottom of the image, emanating from a orange accretion disk surrounding a black hole. Please see the explanation for more detailed information. IXPE Explores a Black Hole Jet Illustration Credit: NASA, Pablo Garcia Explanation: How do black holes create X-rays? Answering this long-standing question was significantly advanced recently with data taken by NASA’s IXPE satellite. X-rays cannot exit a black hole, but they can be created in the energetic environment nearby, in particular by a jet of particles moving outward. By observing X-ray light arriving from near the supermassive black hole at the center of galaxy BL Lac, called a blazar, it was discovered that these X-rays lacked significant polarization, which is expected when created more by energetic electrons than protons. In the featured artistic illustration, a powerful jet is depicted emanating from an orange-colored accretion disk circling the black hole. Understanding highly energetic processes across the universe helps humanity to understand similar processes that occur on or near our Earth. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                                                    [?]grobi » 🌐
                                                    @grobi@defcon.social

                                                    Animation: Spiral Disk around a Black Hole
                                                    Illustrated Animation Credit: ESA, NASA, Hubble, M. Kornmesser
                                                    esahubble.org/projects/anniver
                                                    spacetelescope.org/
                                                    esa.int/
                                                    nasa.gov/

                                                    Explanation:
                                                    What would it look like to orbit a black hole? Many black holes are surrounded by swirling pools of gas known as accretion disks. These disks can be extremely hot, and much of the orbiting gas will eventually fall through the black hole's event horizon -- where it will never be seen again. The featured animation is an artist's rendering of the curious disk spiraling around the supermassive black hole at the center of spiral galaxy NGC 3147. Gas at the inner edge of this disk is so close to the black hole that it moves unusually fast -- at 10 percent of the speed of light. Gas this fast shows relativistic beaming, making the side of the disk heading toward us appear significantly brighter than the side moving away. The animation is based on images of NGC 3147 made recently with the Hubble Space Telescope.

                                                    !>> ascl.net/
                                                    apod.nasa.gov/apod/ap190820.ht

                                                    Alt...2019 August 20 Animation: Spiral Disk around a Black Hole Illustrated Animation Credit: ESA, NASA, Hubble, M. Kornmesser Explanation: What would it look like to orbit a black hole? Many black holes are surrounded by swirling pools of gas known as accretion disks. These disks can be extremely hot, and much of the orbiting gas will eventually fall through the black hole's event horizon -- where it will never be seen again. The featured animation is an artist's rendering of the curious disk spiraling around the supermassive black hole at the center of spiral galaxy NGC 3147. Gas at the inner edge of this disk is so close to the black hole that it moves unusually fast -- at 10 percent of the speed of light. Gas this fast shows relativistic beaming, making the side of the disk heading toward us appear significantly brighter than the side moving away. The animation is based on images of NGC 3147 made recently with the Hubble Space Telescope. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                      [?]grobi » 🌐
                                                      @grobi@defcon.social

                                                      Nearby black holes and their stellar companions form an astrophysical rogues’ gallery

                                                      Stars born with more than about 20 times the Sun’s mass end their lives as black holes. As the name implies, black holes don’t glow on their own because nothing can escape them, not even light. Until 2015, when astronomers first detected merging black holes through the space-time ripples called gravitational waves, the main way to find these ebony enigmas was to search for them in binary systems where they interacted with companion stars. And the best way to do that was to look in X-rays.

                                                      This visualization shows 22 X-ray binaries in our Milky Way galaxy and its nearest neighbor, the Large Magellanic Cloud, that host confirmed stellar-mass black holes. The systems appear at the same physical scale, demonstrating their diversity. Their orbital motion is sped up by nearly 22,000 times, and the viewing angles replicate how we see them from Earth.

                                                      When paired with a star, a black hole can collect matter in two ways. In many cases, a stream of gas can flow directly from the star to the black hole. In others, such as the first confirmed black hole system, Cygnus X-1, the star produces a dense outflow called a stellar wind, some of which the black hole’s intense gravity gathers up. So far, there’s no clear consensus on which mode is used by GRS 1915, the big system at the center of the visualization.

                                                      As it arrives at the black hole, the gas goes into orbit and forms a broad, flattened structure called an accretion disk. GRS 1915’s accretion disk may extend more than 50 million miles (80 million kilometers), greater than the distance separating Mercury from the Sun. Gas in the disk heats up as it slowly spirals inward, glowing in visible, ultraviolet, and finally X-ray light.

                                                      By Francis Reddy
                                                      NASA’s Goddard Space Flight Center, Greenbelt, Md.

                                                      Media contacts:
                                                      Claire Andreoli
                                                      NASA’s Goddard Space Flight Center, Greenbelt, Md.

                                                      Alt...* compressed and converted version This visualization presents 22 X-ray binary systems that host confirmed black holes, all shown at the same scale and with their orbits sped up by about 22,000 times. The view of each system reflects how we see it from Earth. Star colors ranging from blue-white to reddish represent temperatures from 5 times hotter to 45% cooler than our Sun. In most of these systems, a stream of matter from the star forms an accretion disk around the black hole. In others, like the famous system called Cygnus X-1, the star produces a hefty outflow that is partly swept up by the black hole’s gravity to form the disk. The accretion disks use a different color scheme because they sport even higher temperatures than the stars. The largest disk shown, belonging to a binary called GRS 1915, spans a distance greater than that separating Mercury from our Sun. The black holes themselves are shown larger than in reality using spheres scaled to reflect their masses. Download this video in HD formats from NASA’s Scientific Visualization Studio. Credit: NASA’s Goddard Space Flight Center and Scientific Visualization Studio

                                                        [?]grobi » 🌐
                                                        @grobi@defcon.social

                                                        New insights into black hole scattering and gravitational waves unveiled

                                                        Their research provides a high-precision prediction of black hole scattering.

                                                        This research, led by Professor Jan Plefka at Humboldt University of Berlin and Queen Mary University London’s Dr Gustav Mogull, formerly at Humboldt Universität and the Max Planck Institute for Gravitational Physics (Albert Einstein Institute), and conducted in collaboration with an international team of physicists, provides unprecedented precision in calculations crucial to understanding gravitational waves.

                                                        Using cutting-edge techniques inspired by quantum field theory, the team calculated the fifth post-Minkowskian (5PM) order for observables such as scattering angles, radiated energy, and recoil. A groundbreaking aspect of the work is the appearance of Calabi-Yau three-fold periods – geometric structures rooted in string theory and algebraic geometry – within the radiative energy and recoil. These structures, once considered purely mathematical, now find relevance in describing real-world astrophysical phenomena.

                                                        With gravitational wave observatories like LIGO entering a new phase of sensitivity and next-generation detectors such as LISA on the horizon, this research meets the increasing demand for theoretical models of extraordinary accuracy.

                                                        Dr Mogull explained the significance:

                                                        While the physical process of two black holes interacting and scattering via gravity ...
                                                        >>> read more:

                                                        qmul.ac.uk/media/news/2025/sci

                                                        Visualization of the calculated gravitational waves triggered by the scattering of two black holes. Precise models of high-velocity black hole encounters The application of abstract mathematical structures to real-world phenomena provides new insights into gravitational waves An international research team, including scientists from the Max Planck Institute for Gravitational Physics in the Potsdam Science Park, is setting new standards in the modeling of high-speed encounters of black holes. The new method is based on – so far – abstract mathematical structures, the so-called Calabi-Yau spaces. Their application to real astrophysical phenomena now allows extremely accurate predictions of how black holes and neutron stars are deflected from their original orbits after an encounter. The study, published 14. Mai 2025 in Nature, comes at the right time to meet the growing demand for highly accurate theoretical predictions. The results could be used to detect gravitational-wave signals in future observations of the current network of gravitational-wave detectors, with the planned third generation of ground-based observatories such as the Einstein Telescope and Cosmic Explorer, and with the space-based Laser Interferometer Space Antenna (LISA). Credit: Mathias Driesse/Humboldt University Berlin. Working Group "Quantum Field and String Theory" @ Humboldt University

                                                        Alt...Visualization of the calculated gravitational waves triggered by the scattering of two black holes. Precise models of high-velocity black hole encounters The application of abstract mathematical structures to real-world phenomena provides new insights into gravitational waves An international research team, including scientists from the Max Planck Institute for Gravitational Physics in the Potsdam Science Park, is setting new standards in the modeling of high-speed encounters of black holes. The new method is based on – so far – abstract mathematical structures, the so-called Calabi-Yau spaces. Their application to real astrophysical phenomena now allows extremely accurate predictions of how black holes and neutron stars are deflected from their original orbits after an encounter. The study, published 14. Mai 2025 in Nature, comes at the right time to meet the growing demand for highly accurate theoretical predictions. The results could be used to detect gravitational-wave signals in future observations of the current network of gravitational-wave detectors, with the planned third generation of ground-based observatories such as the Einstein Telescope and Cosmic Explorer, and with the space-based Laser Interferometer Space Antenna (LISA). Credit: Mathias Driesse/Humboldt University Berlin. Working Group "Quantum Field and String Theory" @ Humboldt University

                                                          [?]grobi » 🌐
                                                          @grobi@defcon.social

                                                          July 10, 2024

                                                          NASA’s Hubble Finds Strong Evidence for Intermediate-Mass Black Hole in Omega Centauri

                                                          Most known black holes are either extremely massive, like the supermassive black holes that lie at the cores of large galaxies, or relatively lightweight, with a mass of under 100 times that of the Sun. Intermediate-mass black holes (IMBHs) are scarce, however, and are considered rare "missing links" in black hole evolution.

                                                          Now, an international team of astronomers has used more than 500 images from NASA's Hubble Space Telescope — spanning two decades of observations — to search for evidence of an intermediate-mass black hole by following the motion of seven fast-moving stars in the innermost region of the globular star cluster Omega Centauri.

                                                          These stars provide new compelling evidence for the presence of the gravitational pull from an intermediate-mass black hole tugging on them. Only a few other IMBH candidates have been found to date.

                                                          Omega Centauri consists of roughly 10 million stars that are gravitationally bound. The cluster is about 10 times as massive as other big globular clusters — almost as massive as a small galaxy.

                                                          Among the many questions scientists want to answer: Are there any IMBHs, and if so, how common are they? Does a supermassive black hole grow from an IMBH? How do IMBHs themselves form? Are dense star clusters their favored home?

                                                          The astronomers have now created an enormous catalog for the motions of these stars, measuring the velocities for 1.4 million stars gleaned from the Hubble images of the cluster. Most of these observations were intended to calibrate Hubble's instruments rather than for scientific use, but they turned out to be an ideal database for the team's research efforts.
                                                          arxiv.org/abs/2404.03722
                                                          zenodo.org/records/11104046
                                                          [...]

                                                          science.nasa.gov/missions/hubb

                                                          July 10, 2024 Globular cluster Omega Centauri, NGC 5139 An international team of astronomers has used more than 500 images from NASA's Hubble Space Telescope – spanning two decades of observations – to detect seven fast-moving stars in the innermost region of Omega Centauri, the largest and brightest globular cluster in the sky. These stars provide compelling new evidence for the presence of an intermediate-mass black hole (IMBH) tugging on them. Only a few other IMBH candidates have been found to date. This image shows the location of the IMBH in Omega Centauri. If confirmed, at its distance of 17,700 light-years the candidate black hole resides closer to Earth than the 4.3-million-solar-mass black hole in the center of the Milky Way, which is 26,000 light-years away. Besides the Galactic center, it would also be the only known case of a number of stars closely bound to a massive black hole. This image includes three panels. The first image at left shows the globular cluster Omega Centauri, a collection of myriad stars colored red, white, and blue on the black background of space. The second image shows the details of the central region of this cluster, with a closer view of the individual stars. The third image shows the location of the IMBH candidate in the cluster. CREDIT ESA/Hubble, NASA, Maximilian Häberle (MPIA)

                                                          Alt...July 10, 2024 Globular cluster Omega Centauri, NGC 5139 An international team of astronomers has used more than 500 images from NASA's Hubble Space Telescope – spanning two decades of observations – to detect seven fast-moving stars in the innermost region of Omega Centauri, the largest and brightest globular cluster in the sky. These stars provide compelling new evidence for the presence of an intermediate-mass black hole (IMBH) tugging on them. Only a few other IMBH candidates have been found to date. This image shows the location of the IMBH in Omega Centauri. If confirmed, at its distance of 17,700 light-years the candidate black hole resides closer to Earth than the 4.3-million-solar-mass black hole in the center of the Milky Way, which is 26,000 light-years away. Besides the Galactic center, it would also be the only known case of a number of stars closely bound to a massive black hole. This image includes three panels. The first image at left shows the globular cluster Omega Centauri, a collection of myriad stars colored red, white, and blue on the black background of space. The second image shows the details of the central region of this cluster, with a closer view of the individual stars. The third image shows the location of the IMBH candidate in the cluster. CREDIT ESA/Hubble, NASA, Maximilian Häberle (MPIA)

                                                            [?]grobi » 🌐
                                                            @grobi@defcon.social

                                                            [...]

                                                            "We discovered seven stars that should not be there," explained Maximilian Häberle of the Max Planck Institute for Astronomy in Germany, who led this investigation. "They are moving so fast that they would escape the cluster and never come back. The most likely explanation is that a very massive object is gravitationally pulling on these stars and keeping them close to the center. The only object that can be so massive is a black hole, with a mass at least 8,200 times that of our Sun."

                                                            Several studies have suggested the presence of an IMBH in Omega Centauri. However, other studies proposed the mass could be contributed by a central cluster of stellar-mass black holes, and had suggested the lack of fast-moving stars above the necessary escape velocity made an IMBH less likely in comparison.

                                                            "This discovery is the most direct evidence so far of an IMBH in Omega Centauri," added team lead Nadine Neumayer of the Max Planck Institute for Astronomy in Germany, who initiated the study, together with Anil Seth from the University of Utah, Salt Lake City.
                                                            [...]
                                                            If confirmed, at a distance of 17,700 light-years the candidate black hole resides closer to Earth than the 4.3-million-solar-mass black hole in the center of the Milky Way, located 26,000 light-years away.

                                                            Omega Centauri is visible from Earth with the naked eye and is one of the favorite celestial objects for stargazers living in the southern hemisphere. Located just above the plane of the Milky Way, the cluster appears almost as large as the full Moon when seen from a dark rural area. It was first listed in Ptolemy’s catalog nearly 2,000 years ago as a single star. Edmond Halley reported it as a nebula in 1677. In the 1830s the English astronomer John Herschel was the first to recognize it as a globular cluster.

                                                            science.nasa.gov/missions/hubb

                                                            Alt...VIDEO Scientists think a massive object is gravitationally pulling on the stars within Omega Centauri, keeping them close to its center. Credit: NASA's Goddard Space Flight Center, Lead Producer: Paul Morris

                                                              [?]grobi » 🌐
                                                              @grobi@defcon.social

                                                              "Om Nano Paeme Hum ;) "

                                                              2023 June 29

                                                              A Message from the Gravitational Universe
                                                              * Illustration Credit: NANOGrav Physics Frontier Center;
                                                              nanograv.org/
                                                              * Text: Natalia Lewandowska (SUNY Oswego)
                                                              ww1.oswego.edu/physics/

                                                              Explanation:
                                                              Monitoring 68 pulsars with very large radio telescopes, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the arrival times of pulses. These shifts are correlated between different pulsars in a way that indicates that they are caused by GWs. This GW background is likely due to hundreds of thousands or even millions of supermassive black hole binaries. Teams in Europe, Asia and Australia have also independently reported their results today. Previously, the LIGO and Virgo detectors have detected higher-frequency GWs from the merging of individual pairs of massive orbiting objects, such as stellar-mass black holes. The featured illustration highlights this spacetime-shaking result by depicting two orbiting supermassive black holes and several of the pulsars that would appear to have slight timing shifts. The imprint these GWs make on spacetime itself is illustrated
                                                              by a distorted grid.

                                                              en.wikipedia.org/wiki/Radio_te
                                                              nanograv.org/science/overview
                                                              nanograv.org/science/topics/lo
                                                              en.wikipedia.org/wiki/Gravitat
                                                              nanograv.org/news/15yrRelease
                                                              seti.org/news/nanogravs-15-yea
                                                              astrobites.org/2018/01/29/hunt

                                                              apod.nasa.gov/apod/ap230629.ht

                                                              2023 June 29 The illustration shows the beams from pulsars around the image and a pair of merging black holes on the upper left. A grid depicting the warping of spacetime by passing gravitational waves spreads across the image center. A Message from the Gravitational Universe * Illustration Credit: NANOGrav Physics Frontier Center; * Text: Natalia Lewandowska (SUNY Oswego) Explanation: Monitoring 68 pulsars with very large radio telescopes, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the arrival times of pulses. These shifts are correlated between different pulsars in a way that indicates that they are caused by GWs. This GW background is likely due to hundreds of thousands or even millions of supermassive black hole binaries. Teams in Europe, Asia and Australia have also independently reported their results today. Previously, the LIGO and Virgo detectors have detected higher-frequency GWs from the merging of individual pairs of massive orbiting objects, such as stellar-mass black holes. The featured illustration highlights this spacetime-shaking result by depicting two orbiting supermassive black holes and several of the pulsars that would appear to have slight timing shifts. The imprint these GWs make on spacetime itself is illustrated by a distorted grid. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)

                                                              Alt...2023 June 29 The illustration shows the beams from pulsars around the image and a pair of merging black holes on the upper left. A grid depicting the warping of spacetime by passing gravitational waves spreads across the image center. A Message from the Gravitational Universe * Illustration Credit: NANOGrav Physics Frontier Center; * Text: Natalia Lewandowska (SUNY Oswego) Explanation: Monitoring 68 pulsars with very large radio telescopes, the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has uncovered evidence for the gravitational wave (GW) background by carefully measuring slight shifts in the arrival times of pulses. These shifts are correlated between different pulsars in a way that indicates that they are caused by GWs. This GW background is likely due to hundreds of thousands or even millions of supermassive black hole binaries. Teams in Europe, Asia and Australia have also independently reported their results today. Previously, the LIGO and Virgo detectors have detected higher-frequency GWs from the merging of individual pairs of massive orbiting objects, such as stellar-mass black holes. The featured illustration highlights this spacetime-shaking result by depicting two orbiting supermassive black holes and several of the pulsars that would appear to have slight timing shifts. The imprint these GWs make on spacetime itself is illustrated by a distorted grid. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)

                                                                [?]grobi » 🌐
                                                                @grobi@defcon.social

                                                                2018 December 3

                                                                Spiraling Supermassive Black Holes
                                                                * Video Credit: NASA's Goddard Space Flight Center
                                                                nasa.gov/
                                                                nasa.gov/goddard
                                                                * Music: In the Hall of the Mountain King by Edvard Grieg
                                                                en.wikipedia.org/wiki/In_the_H
                                                                en.wikipedia.org/wiki/Edvard_G

                                                                Explanation:
                                                                Do black holes glow when they collide? When merging, co-orbiting black holes are sure to emit a burst of unusual gravitational radiation, but will they emit light, well before that, if they are surrounded by gas? To help find out, astrophysicists created a sophisticated computer simulation. The simulation and featured resulting video accurately depicts two spiraling supermassive black holes, including the effects of Einstein's general relativity on the surrounding gas and light. The video first shows the system from the top, and later from the side where unusual gravitational lens distortions are more prominent. Numerical results indicate that gravitational and magnetic forces should energize the gas to emit high-energy light from the ultraviolet to the X-ray. The emission of such light may enable humanity to detect and study supermassive black hole pairs well before they spiral together.

                                                                apod.nasa.gov/apod/ap181203.ht

                                                                Alt...2018 December 3 Spiraling Supermassive Black Holes * Video Credit: NASA's Goddard Space Flight Center; * Music: In the Hall of the Mountain King by Edvard Grieg Explanation: Do black holes glow when they collide? When merging, co-orbiting black holes are sure to emit a burst of unusual gravitational radiation, but will they emit light, well before that, if they are surrounded by gas? To help find out, astrophysicists created a sophisticated computer simulation. The simulation and featured resulting video accurately depicts two spiraling supermassive black holes, including the effects of Einstein's general relativity on the surrounding gas and light. The video first shows the system from the top, and later from the side where unusual gravitational lens distortions are more prominent. Numerical results indicate that gravitational and magnetic forces should energize the gas to emit high-energy light from the ultraviolet to the X-ray. The emission of such light may enable humanity to detect and study supermassive black hole pairs well before they spiral together. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                  [?]grobi » 🌐
                                                                  @grobi@defcon.social

                                                                  2021 December 7

                                                                  Ninety Gravitational Wave Spectrograms and Counting
                                                                  * Image Credit: NSF, LIGO, VIRGO, KAGRA, Georgia Tech, Vanderbilt U.
                                                                  nsf.gov/
                                                                  ligo.org/about.php
                                                                  public.virgo-gw.eu/the-virgo-c
                                                                  gwcenter.icrr.u-tokyo.ac.jp/en
                                                                  physics.gatech.edu/
                                                                  as.vanderbilt.edu/physics/
                                                                  * Graphic : Sudarshan Ghonge & Karan Jani
                                                                  humansofligo.blogspot.com/2019
                                                                  karanjani.com/

                                                                  Explanation:
                                                                  Every time two massive black holes collide, a loud chirping sound is broadcast out into the universe in gravitational waves. Humanity has only had the technology to hear these unusual chirps for the past seven years, but since then we have heard about 90 -- during the first three observing runs. Featured above are the spectrograms -- plots of gravitational-wave frequency versus time -- of these 90 as detected by the giant detectors of LIGO (in the USA), VIRGO (in Europe), and KAGRA (in Japan). The more energy received on Earth from a collision, the brighter it appears on the graphic. Among many science firsts, these gravitational-radiation chirps are giving humanity an unprecedented inventory of black holes and neutron stars, and a new way to measure the expansion rate of our universe. A fourth gravitational wave observing run with increased sensitivity is currently planned to begin in 2022 December.

                                                                  spaceplace.nasa.gov/gravitatio

                                                                  dcc.ligo.org/LIGO-G2102338/pub
                                                                  ligo.org/science-summaries/O3b

                                                                  apod.nasa.gov/apod/ap211207.ht

                                                                  2021 December 7 The featured image shows spectrograms for the first 90 gravitational wave events ever detected. Ninety Gravitational Wave Spectrograms and Counting * Image Credit: NSF, LIGO, VIRGO, KAGRA, Georgia Tech, Vanderbilt U. * Graphic : Sudarshan Ghonge & Karan Jani Explanation: Every time two massive black holes collide, a loud chirping sound is broadcast out into the universe in gravitational waves. Humanity has only had the technology to hear these unusual chirps for the past seven years, but since then we have heard about 90 -- during the first three observing runs. Featured above are the spectrograms -- plots of gravitational-wave frequency versus time -- of these 90 as detected by the giant detectors of LIGO (in the USA), VIRGO (in Europe), and KAGRA (in Japan). The more energy received on Earth from a collision, the brighter it appears on the graphic. Among many science firsts, these gravitational-radiation chirps are giving humanity an unprecedented inventory of black holes and neutron stars, and a new way to measure the expansion rate of our universe. A fourth gravitational wave observing run with increased sensitivity is currently planned to begin in 2022 December. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                  Alt...2021 December 7 The featured image shows spectrograms for the first 90 gravitational wave events ever detected. Ninety Gravitational Wave Spectrograms and Counting * Image Credit: NSF, LIGO, VIRGO, KAGRA, Georgia Tech, Vanderbilt U. * Graphic : Sudarshan Ghonge & Karan Jani Explanation: Every time two massive black holes collide, a loud chirping sound is broadcast out into the universe in gravitational waves. Humanity has only had the technology to hear these unusual chirps for the past seven years, but since then we have heard about 90 -- during the first three observing runs. Featured above are the spectrograms -- plots of gravitational-wave frequency versus time -- of these 90 as detected by the giant detectors of LIGO (in the USA), VIRGO (in Europe), and KAGRA (in Japan). The more energy received on Earth from a collision, the brighter it appears on the graphic. Among many science firsts, these gravitational-radiation chirps are giving humanity an unprecedented inventory of black holes and neutron stars, and a new way to measure the expansion rate of our universe. A fourth gravitational wave observing run with increased sensitivity is currently planned to begin in 2022 December. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                    [?]grobi » 🌐
                                                                    @grobi@defcon.social

                                                                    The Sound of Two Black Holes Colliding

                                                                    Gravitational waves sent out from a pair of colliding black holes have been converted to sound waves, as heard in this animation. On September 14, 2015, LIGO observed gravitational waves from the merger of two black holes, each about 30 times the mass of our sun. The incredibly powerful event, which released 50 times more energy than all the stars in the observable universe, lasted only fractions of a second.

                                                                    In the first two runs of the animation, the sound-wave frequencies exactly match the frequencies of the gravitational waves. The second two runs of the animation play the sounds again at higher frequencies that better fit the human hearing range. The animation ends by playing the original frequencies again twice.

                                                                    As the black holes spiral closer and closer in together, the frequency of the gravitational waves increases. Scientists call these sounds "chirps," because some events that generate gravitation waves would sound like a bird's chirp.

                                                                    Audio Credit:
                                                                    Caltech/MIT/LIGO Lab
                                                                    ligo.caltech.edu

                                                                    Alt...The Sound of Two Black Holes Colliding Gravitational waves sent out from a pair of colliding black holes have been converted to sound waves, as heard in this animation. On September 14, 2015, LIGO observed gravitational waves from the merger of two black holes, each about 30 times the mass of our sun. The incredibly powerful event, which released 50 times more energy than all the stars in the observable universe, lasted only fractions of a second. In the first two runs of the animation, the sound-wave frequencies exactly match the frequencies of the gravitational waves. The second two runs of the animation play the sounds again at higher frequencies that better fit the human hearing range. The animation ends by playing the original frequencies again twice. As the black holes spiral closer and closer in together, the frequency of the gravitational waves increases. Scientists call these sounds "chirps," because some events that generate gravitation waves would sound like a bird's chirp. Audio Credit: Caltech/MIT/LIGO Lab ligo.caltech.edu

                                                                      [?]grobi » 🌐
                                                                      @grobi@defcon.social

                                                                      2017 March 27

                                                                      Black Hole Accreting with Jet
                                                                      * Illustration Credit: NASA, Swift, Aurore Simonnet (Sonoma State U.)
                                                                      nasa.gov/
                                                                      nasa.gov/mission_pages/swift/m
                                                                      universe.sonoma.edu/~aurore/ab
                                                                      phys-astro.sonoma.edu/index.sh

                                                                      Explanation:
                                                                      What happens when a black hole devours a star? Many details remain unknown, but recent observations are providing new clues. In 2014, a powerful explosion was recorded by the ground-based robotic telescopes of the All Sky Automated Survey for SuperNovae (ASAS-SN) project, and followed up by instruments including NASA's Earth-orbiting Swift satellite. Computer modeling of these emissions fit a star being ripped apart by a distant supermassive black hole. The results of such a collision are portrayed in the featured artistic illustration. The black hole itself is a depicted as a tiny black dot in the center. As matter falls toward the hole, it collides with other matter and heats up. Surrounding the black hole is an accretion disk of hot matter that used to be the star, with a jet emanating from the black hole's spin axis.

                                                                      astronomy.ohio-state.edu/asass

                                                                      apod.nasa.gov/apod/ap170327.ht

                                                                      2017 March 27 Black Hole Accreting with Jet * Illustration Credit: NASA, Swift, Aurore Simonnet (Sonoma State U.) Explanation: What happens when a black hole devours a star? Many details remain unknown, but recent observations are providing new clues. In 2014, a powerful explosion was recorded by the ground-based robotic telescopes of the All Sky Automated Survey for SuperNovae (ASAS-SN) project, and followed up by instruments including NASA's Earth-orbiting Swift satellite. Computer modeling of these emissions fit a star being ripped apart by a distant supermassive black hole. The results of such a collision are portrayed in the featured artistic illustration. The black hole itself is a depicted as a tiny black dot in the center. As matter falls toward the hole, it collides with other matter and heats up. Surrounding the black hole is an accretion disk of hot matter that used to be the star, with a jet emanating from the black hole's spin axis. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                      Alt...2017 March 27 Black Hole Accreting with Jet * Illustration Credit: NASA, Swift, Aurore Simonnet (Sonoma State U.) Explanation: What happens when a black hole devours a star? Many details remain unknown, but recent observations are providing new clues. In 2014, a powerful explosion was recorded by the ground-based robotic telescopes of the All Sky Automated Survey for SuperNovae (ASAS-SN) project, and followed up by instruments including NASA's Earth-orbiting Swift satellite. Computer modeling of these emissions fit a star being ripped apart by a distant supermassive black hole. The results of such a collision are portrayed in the featured artistic illustration. The black hole itself is a depicted as a tiny black dot in the center. As matter falls toward the hole, it collides with other matter and heats up. Surrounding the black hole is an accretion disk of hot matter that used to be the star, with a jet emanating from the black hole's spin axis. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

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                                                                        @grobi@defcon.social

                                                                        2025 September 23

                                                                        NGC 6357: Cathedral to Massive Stars
                                                                        * Image Credit: NASA, ESA, CSA, STScI, JWST
                                                                        nasa.gov/
                                                                        esa.int/
                                                                        asc-csa.gc.ca/eng/
                                                                        stsci.edu/
                                                                        science.nasa.gov/mission/webb/
                                                                        * Processing: Alyssa Pagan (STScI)
                                                                        friendsofnasa.org/2023/03/behi
                                                                        * Rollover: NASA, ESA, HST, & J. M. Apellániz (IAA, Spain)
                                                                        iaa.es/
                                                                        * Acknowledgement: D. De Martin (ESA/Hubble)
                                                                        esahubble.org/

                                                                        Explanation:
                                                                        How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known. This star is the brightest object located in the central cavity near the bottom center of the featured image taken with the Webb Space Telescope in infrared light. For comparison, a rollover image from the Hubble Space Telescope is also featured in visible light. Close inspection of the images, however, has shown that Pismis 24-1 derives its brilliant luminosity not from a single star but from three at least. Component stars would still remain near 100 solar masses, making them among the more massive stars currently on record. Toward the bottom of the image, stars are still forming in the associated emission nebula NGC 6357. Appearing perhaps like a Gothic cathedral, energetic stars near the center appear to be breaking out and illuminating a spectacular cocoon.

                                                                        apod.nasa.gov/apod/ap250923.ht

                                                                        2025 September 23 Stars dot the frame that has a blue background. Covering the lower part of the image, and the far right, are brown and tan nebular structures. NGC 6357: Cathedral to Massive Stars * Image Credit: NASA, ESA, CSA, STScI, JWST * Processing: Alyssa Pagan (STScI) * Rollover: NASA, ESA, HST, & J. M. Apellániz (IAA, Spain) * Acknowledgement: D. De Martin (ESA/Hubble) Explanation: How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known. This star is the brightest object located in the central cavity near the bottom center of the featured image taken with the Webb Space Telescope in infrared light. For comparison, a rollover image from the Hubble Space Telescope is also featured in visible light. Close inspection of the images, however, has shown that Pismis 24-1 derives its brilliant luminosity not from a single star but from three at least. Component stars would still remain near 100 solar masses, making them among the more massive stars currently on record. Toward the bottom of the image, stars are still forming in the associated emission nebula NGC 6357. Appearing perhaps like a Gothic cathedral, energetic stars near the center appear to be breaking out and illuminating a spectacular cocoon. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)

                                                                        Alt...2025 September 23 Stars dot the frame that has a blue background. Covering the lower part of the image, and the far right, are brown and tan nebular structures. NGC 6357: Cathedral to Massive Stars * Image Credit: NASA, ESA, CSA, STScI, JWST * Processing: Alyssa Pagan (STScI) * Rollover: NASA, ESA, HST, & J. M. Apellániz (IAA, Spain) * Acknowledgement: D. De Martin (ESA/Hubble) Explanation: How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it one of the most massive stars known. This star is the brightest object located in the central cavity near the bottom center of the featured image taken with the Webb Space Telescope in infrared light. For comparison, a rollover image from the Hubble Space Telescope is also featured in visible light. Close inspection of the images, however, has shown that Pismis 24-1 derives its brilliant luminosity not from a single star but from three at least. Component stars would still remain near 100 solar masses, making them among the more massive stars currently on record. Toward the bottom of the image, stars are still forming in the associated emission nebula NGC 6357. Appearing perhaps like a Gothic cathedral, energetic stars near the center appear to be breaking out and illuminating a spectacular cocoon. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)

                                                                        WEBB Infrared Light Image

                                                                        Alt...WEBB Infrared Light Image

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                                                                          @grobi@defcon.social

                                                                          2010 March 21

                                                                          Equinox + 1
                                                                          * Credit & Copyright: Joe Orman
                                                                          joeorman.net/Gallery.html

                                                                          Explanation:
                                                                          Twice a year, at the Spring and Fall equinox, the Sun rises due east. In an emphatic demonstration of this celestial alignment, photographer Joe Orman recorded this inspiring image of the Sun rising exactly along the east-west oriented Western Canal, in Tempe, Arizona, USA. But he waited until one day after the northern Spring equinox, in 2001, to photograph the striking view. Why was the rising Sun due east one day after the equinox? At Tempe's latitude the Sun rises at an angle, arcing southward as it climbs above the horizon. Because the distant mountains hide the true horizon, the Sun shifts slightly southward by the time it clears the mountain tops. Waiting 24 hours allowed the Sun to rise just north of east and arc back to an exactly eastern alignment for the photo. Today is another Equinox + 1 day, with the Sun crossing the celestial equator yesterday at about 17:32 Universal Time.
                                                                          joeorman.net/Sun/Sun_010321_2.
                                                                          joeorman.net/Sun/Sun_05.html

                                                                          apod.nasa.gov/apod/ap100321.ht

                                                                          2010 March 21 Equinox + 1 * Credit & Copyright: Joe Orman Explanation: Twice a year, at the Spring and Fall equinox, the Sun rises due east. In an emphatic demonstration of this celestial alignment, photographer Joe Orman recorded this inspiring image of the Sun rising exactly along the east-west oriented Western Canal, in Tempe, Arizona, USA. But he waited until one day after the northern Spring equinox, in 2001, to photograph the striking view. Why was the rising Sun due east one day after the equinox? At Tempe's latitude the Sun rises at an angle, arcing southward as it climbs above the horizon. Because the distant mountains hide the true horizon, the Sun shifts slightly southward by the time it clears the mountain tops. Waiting 24 hours allowed the Sun to rise just north of east and arc back to an exactly eastern alignment for the photo. Today is another Equinox + 1 day, with the Sun crossing the celestial equator yesterday at about 17:32 Universal Time. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                          Alt...2010 March 21 Equinox + 1 * Credit & Copyright: Joe Orman Explanation: Twice a year, at the Spring and Fall equinox, the Sun rises due east. In an emphatic demonstration of this celestial alignment, photographer Joe Orman recorded this inspiring image of the Sun rising exactly along the east-west oriented Western Canal, in Tempe, Arizona, USA. But he waited until one day after the northern Spring equinox, in 2001, to photograph the striking view. Why was the rising Sun due east one day after the equinox? At Tempe's latitude the Sun rises at an angle, arcing southward as it climbs above the horizon. Because the distant mountains hide the true horizon, the Sun shifts slightly southward by the time it clears the mountain tops. Waiting 24 hours allowed the Sun to rise just north of east and arc back to an exactly eastern alignment for the photo. Today is another Equinox + 1 day, with the Sun crossing the celestial equator yesterday at about 17:32 Universal Time. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                            [?]grobi » 🌐
                                                                            @grobi@defcon.social

                                                                            2025 September 21

                                                                            Equinox Sunset
                                                                            * Image Credit: Luca Vanzella
                                                                            flickr.com/people/53851348@N05/

                                                                            Explanation:
                                                                            Does the Sun set in the same direction every day? No, the direction of sunset depends on the time of the year. Although the Sun always sets approximately toward the west, on an equinox like tomorrow the Sun sets directly toward the west. After tomorrow's September equinox, the Sun will set increasingly toward the southwest, reaching its maximum displacement at the December solstice. Before tomorrow's (today's) September equinox, the Sun had set toward the northwest, reaching its maximum displacement at the June solstice. The featured time-lapse image shows seven bands of the Sun setting one day each month from 2019 December through 2020 June. These image sequences were taken from Alberta, Canada -- well north of the Earth's equator -- and feature the city of Edmonton in the foreground. The middle band shows the Sun setting during an equinox -- in March. From this location, the Sun will set along this same equinox band again tomorrow.

                                                                            earthsky.org/astronomy-essenti

                                                                            apod.nasa.gov/apod/ap250921.ht

                                                                            2025 September 21 A city skyline is shown behind some hills and a river. The path of the Sun is shown for several times during a year. Equinox Sunset * Image Credit: Luca Vanzella Explanation: Does the Sun set in the same direction every day? No, the direction of sunset depends on the time of the year. Although the Sun always sets approximately toward the west, on an equinox like tomorrow the Sun sets directly toward the west. After tomorrow's September equinox, the Sun will set increasingly toward the southwest, reaching its maximum displacement at the December solstice. Before tomorrow's September equinox, the Sun had set toward the northwest, reaching its maximum displacement at the June solstice. The featured time-lapse image shows seven bands of the Sun setting one day each month from 2019 December through 2020 June. These image sequences were taken from Alberta, Canada -- well north of the Earth's equator -- and feature the city of Edmonton in the foreground. The middle band shows the Sun setting during an equinox -- in March. From this location, the Sun will set along this same equinox band again tomorrow. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                                                                            Alt...2025 September 21 A city skyline is shown behind some hills and a river. The path of the Sun is shown for several times during a year. Equinox Sunset * Image Credit: Luca Vanzella Explanation: Does the Sun set in the same direction every day? No, the direction of sunset depends on the time of the year. Although the Sun always sets approximately toward the west, on an equinox like tomorrow the Sun sets directly toward the west. After tomorrow's September equinox, the Sun will set increasingly toward the southwest, reaching its maximum displacement at the December solstice. Before tomorrow's September equinox, the Sun had set toward the northwest, reaching its maximum displacement at the June solstice. The featured time-lapse image shows seven bands of the Sun setting one day each month from 2019 December through 2020 June. These image sequences were taken from Alberta, Canada -- well north of the Earth's equator -- and feature the city of Edmonton in the foreground. The middle band shows the Sun setting during an equinox -- in March. From this location, the Sun will set along this same equinox band again tomorrow. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                                                                              [?]grobi » 🌐
                                                                              @grobi@defcon.social

                                                                              2014 March 19

                                                                              Equinox on a Spinning Earth
                                                                              * Image Credit: NASA, Meteosat, Robert Simmon
                                                                              nasa.gov/
                                                                              eumetsat.int/website/home/Sate
                                                                              nasa.gov/centers/goddard/about

                                                                              Explanation:
                                                                              When does the line between day and night become vertical? Tomorrow. Tomorrow is an equinox on planet Earth, a time of year when day and night are most nearly equal. At an equinox, the Earth's terminator -- the dividing line between day and night -- becomes vertical and connects the north and south poles. The above time-lapse video demonstrates this by displaying an entire year on planet Earth in twelve seconds. From geosynchronous orbit, the Meteosat satellite recorded these infrared images of the Earth every day at the same local time. The video started at the September 2010 equinox with the terminator line being vertical. As the Earth revolved around the Sun, the terminator was seen to tilt in a way that provides less daily sunlight to the northern hemisphere, causing winter in the north. As the year progressed, the March 2011 equinox arrived halfway through the video, followed by the terminator tilting the other way, causing winter in the southern hemisphere -- and summer in the north. The captured year ends again with the September equinox, concluding another of billions of trips the Earth has taken -- and will take -- around the Sun.
                                                                              en.wikipedia.org/wiki/Equinox
                                                                              !>>earthsky.org/astronomy-essenti

                                                                              apod.nasa.gov/apod/ap140319.ht

                                                                              Alt...2014 March 19 Equinox on a Spinning Earth * Image Credit: NASA, Meteosat, Robert Simmon Explanation: When does the line between day and night become vertical? Tomorrow. Tomorrow is an equinox on planet Earth, a time of year when day and night are most nearly equal. At an equinox, the Earth's terminator -- the dividing line between day and night -- becomes vertical and connects the north and south poles. The above time-lapse video demonstrates this by displaying an entire year on planet Earth in twelve seconds. From geosynchronous orbit, the Meteosat satellite recorded these infrared images of the Earth every day at the same local time. The video started at the September 2010 equinox with the terminator line being vertical. As the Earth revolved around the Sun, the terminator was seen to tilt in a way that provides less daily sunlight to the northern hemisphere, causing winter in the north. As the year progressed, the March 2011 equinox arrived halfway through the video, followed by the terminator tilting the other way, causing winter in the southern hemisphere -- and summer in the north. The captured year ends again with the September equinox, concluding another of billions of trips the Earth has taken -- and will take -- around the Sun. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                                [?]grobi » 🌐
                                                                                @grobi@defcon.social

                                                                                TOPIC> Sunrises & Sunsets

                                                                                2016 March 20

                                                                                A Picturesque Equinox Sunset
                                                                                * Image Credit & Copyright: Roland Christen

                                                                                Explanation:
                                                                                What's that at the end of the road? The Sun. Many towns have roads that run east - west, and on two days each year, the Sun rises and sets right down the middle. Today is one of those days: an equinox. Not only is today a day of equal night ("aequus"-"nox") and day time, but also a day when the sun rises precisely to the east and sets due west. Featured here is a picturesque road in northwest Illinois, USA that runs approximately east -west. The image was taken one year ago today, during the March Equinox of 2015, and shows the Sun down the road at sunset. In many cultures, this March equinox is taken to be the first day of a season, typically spring in Earth's northern hemisphere, and autumn in the south. Does your favorite street run east - west? Tonight at sunset, with a quick glance, you can actually find out.
                                                                                en.wiktionary.org/wiki/equinox
                                                                                en.wikipedia.org/wiki/March_eq

                                                                                scijinks.gov/solstice/
                                                                                earthobservatory.nasa.gov/imag

                                                                                apod.nasa.gov/apod/ap160320.ht

                                                                                2016 March 20 A Picturesque Equinox Sunset * Image Credit & Copyright: Roland Christen Explanation: What's that at the end of the road? The Sun. Many towns have roads that run east - west, and on two days each year, the Sun rises and sets right down the middle. Today is one of those days: an equinox. Not only is today a day of equal night ("aequus"-"nox") and day time, but also a day when the sun rises precisely to the east and sets due west. Featured here is a picturesque road in northwest Illinois, USA that runs approximately east -west. The image was taken one year ago today, during the March Equinox of 2015, and shows the Sun down the road at sunset. In many cultures, this March equinox is taken to be the first day of a season, typically spring in Earth's northern hemisphere, and autumn in the south. Does your favorite street run east - west? Tonight at sunset, with a quick glance, you can actually find out. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                                Alt...2016 March 20 A Picturesque Equinox Sunset * Image Credit & Copyright: Roland Christen Explanation: What's that at the end of the road? The Sun. Many towns have roads that run east - west, and on two days each year, the Sun rises and sets right down the middle. Today is one of those days: an equinox. Not only is today a day of equal night ("aequus"-"nox") and day time, but also a day when the sun rises precisely to the east and sets due west. Featured here is a picturesque road in northwest Illinois, USA that runs approximately east -west. The image was taken one year ago today, during the March Equinox of 2015, and shows the Sun down the road at sunset. In many cultures, this March equinox is taken to be the first day of a season, typically spring in Earth's northern hemisphere, and autumn in the south. Does your favorite street run east - west? Tonight at sunset, with a quick glance, you can actually find out. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                                  [?]grobi » 🌐
                                                                                  @grobi@defcon.social

                                                                                  TOPIC> Saturn

                                                                                  2025 September 22

                                                                                  The planet Saturn is pictured 6 times in a horizonal column, labelled by years with 2020 at the top and 2025 at the bottom. As the years progress, Saturn's ring appear less prominent.

                                                                                  Equinox at Saturn
                                                                                  * Image Credit & Copyright: Imran Sultan
                                                                                  instagram.com/imran.astro/

                                                                                  Explanation:
                                                                                  On Saturn, the rings tell you the season. On Earth, today marks an equinox, the time when the Earth's equator tilts directly toward the Sun. Since Saturn's grand rings orbit along the planet's equator, these rings appear most prominent -- from the direction of the Sun -- when the spin axis of Saturn points toward the Sun. Conversely, when Saturn's spin axis points to the side, an equinox occurs, and the edge-on rings are hard to see from not only the Sun -- but Earth. In the featured montage, images of Saturn between the years of 2020 and 2025 have been superposed to show the giant planet passing, with this year's equinox, from summer in the north to summer in the south. Yesterday, Saturn was coincidently about as close as it gets to planet Earth, and so this month the ringed giant's orb is relatively bright and visible throughout the night.
                                                                                  instagram.com/p/DOuLq6ADsV4/

                                                                                  spaceplace.nasa.gov/saturn-rin

                                                                                  apod.nasa.gov/apod/ap250922.ht
                                                                                  science.nasa.gov/saturn/
                                                                                  apod.nasa.gov/apod/ap250429.ht

                                                                                  2025 September 22 The planet Saturn is pictured 6 times in a horizonal column, labelled by years with 2020 at the top and 2025 at the bottom. As the years progress, Saturn's ring appear less prominent. Equinox at Saturn * Image Credit & Copyright: Imran Sultan Explanation: On Saturn, the rings tell you the season. On Earth, today marks an equinox, the time when the Earth's equator tilts directly toward the Sun. Since Saturn's grand rings orbit along the planet's equator, these rings appear most prominent -- from the direction of the Sun -- when the spin axis of Saturn points toward the Sun. Conversely, when Saturn's spin axis points to the side, an equinox occurs, and the edge-on rings are hard to see from not only the Sun -- but Earth. In the featured montage, images of Saturn between the years of 2020 and 2025 have been superposed to show the giant planet passing, with this year's equinox, from summer in the north to summer in the south. Yesterday, Saturn was coincidently about as close as it gets to planet Earth, and so this month the ringed giant's orb is relatively bright and visible throughout the night. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                                                                                  Alt...2025 September 22 The planet Saturn is pictured 6 times in a horizonal column, labelled by years with 2020 at the top and 2025 at the bottom. As the years progress, Saturn's ring appear less prominent. Equinox at Saturn * Image Credit & Copyright: Imran Sultan Explanation: On Saturn, the rings tell you the season. On Earth, today marks an equinox, the time when the Earth's equator tilts directly toward the Sun. Since Saturn's grand rings orbit along the planet's equator, these rings appear most prominent -- from the direction of the Sun -- when the spin axis of Saturn points toward the Sun. Conversely, when Saturn's spin axis points to the side, an equinox occurs, and the edge-on rings are hard to see from not only the Sun -- but Earth. In the featured montage, images of Saturn between the years of 2020 and 2025 have been superposed to show the giant planet passing, with this year's equinox, from summer in the north to summer in the south. Yesterday, Saturn was coincidently about as close as it gets to planet Earth, and so this month the ringed giant's orb is relatively bright and visible throughout the night. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                                                                                    [?]Danish Akhtar » 🌐
                                                                                    @danish_akhtar7@mastodon.social

                                                                                    If, in a hypothetical situation, a benevolent Alien race comes to Earth & says that Earth will be annihilated by a gamma-ray burst in 5 years, which will be affirmed by NASA. 

                                                                                    They are moving the entire human population to a habitable planet in another place. How will you react? Will you buy it?

                                                                                      [?]grobi » 🌐
                                                                                      @grobi@defcon.social

                                                                                      How NASA’s Roman Mission Will Unveil Our Home Galaxy Using

                                                                                      Cosmic Dust
                                                                                      - NASA / Ashley Balzer

                                                                                      NASA’s Nancy Grace Roman Space Telescope will help scientists better understand our Milky Way galaxy’s less sparkly components — gas and dust strewn between stars, known as the interstellar medium.

                                                                                      One of Roman’s major observing programs, called the Galactic Plane Survey, will peer through our galaxy to its most distant edge, mapping roughly 20 billion stars—about four times more than have currently been mapped. Scientists will use data from these stars to study and map the dust their light travels through, contributing to the most complete picture yet of the Milky Way’s structure, star formation, and the origins of our solar system. [...]

                                                                                      Scientists know how our galaxy likely looks by combining observations of the Milky Way and other spiral galaxies. But dust clouds make it hard to work out the details on the opposite side of our galaxy. Imagine trying to map a neighborhood while looking through the windows of a house surrounded by a dense fog.

                                                                                      Roman will see through the “fog” of dust using a specialized camera and filters that observe infrared light — light with longer wavelengths than our eyes can detect. Infrared light is more likely to pass through dust clouds without scattering.

                                                                                      Light with shorter wavelengths, including blue light produced by stars, more easily scatters. That means stars shining through dust appear dimmer and redder than they actually are.

                                                                                      By comparing the observations with information on the source star’s characteristics, astronomers can disentangle the star’s distance from how much its colors have been reddened. Studying those effects reveals clues about the dust’s properties. [...]

                                                                                      * Credit: NASA/Laine Havens
                                                                                      * Music credit: Building Heroes by Enrico Cacace [BMI], Universal Production Music

                                                                                      nasa.gov/missions/roman-space-

                                                                                      Alt...Our Milky Way galaxy is home to more than 100 billion stars that are often separated by trillions of miles. The spaces in between, called the interstellar medium, aren’t empty — they’re sprinkled with gas and dust that are both the seeds of new stars and the leftover crumbs from stars long dead. Studying the interstellar medium with observatories like NASA’s upcoming Nancy Grace Roman Space Telescope will reveal new insight into the galactic dust recycling system. * Credit: NASA/Laine Havens * Music credit: Building Heroes by Enrico Cacace [BMI], Universal Production Music

                                                                                        [?]grobi » 🌐
                                                                                        @grobi@defcon.social

                                                                                        2005 December 23

                                                                                        Hydrogen and Dust in the Rosette Nebula
                                                                                        * Credit: Nick Wright (University College London), IPHAS Collaboration
                                                                                        ucl.ac.uk/mathematical-physica
                                                                                        imperial.ac.uk/astrophysics

                                                                                        Explanation:
                                                                                        At the edge of a large molecular cloud in Monoceros, some 3,000 light years away, dark filaments of dust are silhouetted by luminous hydrogen gas. The close up view of the Rosette Nebula dramatically suggests that star formation is an on going process in the region, with dark filaments sculpted by winds and radiation from hot, young stars. Ultraviolet radiation from the young stars also strips electrons from the surrounding hydrogen atoms. As electrons and atoms recombine they emit longer wavelength, lower energy light in a well known characteristic pattern of bright spectral lines. At visible wavelengths, the strongest emission line in this pattern is in the red part of the spectrum and is known as "Hydrogen-alpha" or just H-alpha. Part of IPHAS, a survey of H-alpha emission in our Milky Way Galaxy, this image spans about 25 light-years.

                                                                                        apod.nasa.gov/apod/ap051223.ht

                                                                                        2005 December 23 Hydrogen and Dust in the Rosette Nebula * Credit: Nick Wright (University College London), IPHAS Collaboration Explanation: At the edge of a large molecular cloud in Monoceros, some 3,000 light years away, dark filaments of dust are silhouetted by luminous hydrogen gas. The close up view of the Rosette Nebula dramatically suggests that star formation is an on going process in the region, with dark filaments sculpted by winds and radiation from hot, young stars. Ultraviolet radiation from the young stars also strips electrons from the surrounding hydrogen atoms. As electrons and atoms recombine they emit longer wavelength, lower energy light in a well known characteristic pattern of bright spectral lines. At visible wavelengths, the strongest emission line in this pattern is in the red part of the spectrum and is known as "Hydrogen-alpha" or just H-alpha. Part of IPHAS, a survey of H-alpha emission in our Milky Way Galaxy, this image spans about 25 light-years. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA) NASA Web Site Statements, Warnings, and Disclaimers NASA Official: Jay Norris. Specific rights apply. A service of: EUD at NASA / GSFC & Michigan Tech. U.

                                                                                        Alt...2005 December 23 Hydrogen and Dust in the Rosette Nebula * Credit: Nick Wright (University College London), IPHAS Collaboration Explanation: At the edge of a large molecular cloud in Monoceros, some 3,000 light years away, dark filaments of dust are silhouetted by luminous hydrogen gas. The close up view of the Rosette Nebula dramatically suggests that star formation is an on going process in the region, with dark filaments sculpted by winds and radiation from hot, young stars. Ultraviolet radiation from the young stars also strips electrons from the surrounding hydrogen atoms. As electrons and atoms recombine they emit longer wavelength, lower energy light in a well known characteristic pattern of bright spectral lines. At visible wavelengths, the strongest emission line in this pattern is in the red part of the spectrum and is known as "Hydrogen-alpha" or just H-alpha. Part of IPHAS, a survey of H-alpha emission in our Milky Way Galaxy, this image spans about 25 light-years. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA) NASA Web Site Statements, Warnings, and Disclaimers NASA Official: Jay Norris. Specific rights apply. A service of: EUD at NASA / GSFC & Michigan Tech. U.

                                                                                          [?]grobi » 🌐
                                                                                          @grobi@defcon.social

                                                                                          2016 November 19

                                                                                          IC 5070: A Dusty Pelican in the Swan
                                                                                          * Image Credit & Copyright: Steve Richards (Chanctonbury Observatory)

                                                                                          Explanation:
                                                                                          The recognizable profile of the Pelican Nebula soars nearly 2,000 light-years away in the high flying constellation Cygnus, the Swan. Also known as IC 5070, this interstellar cloud of gas and dust is appropriately found just off the "east coast" of the North America Nebula (NGC 7000), another surprisingly familiar looking emission nebula in Cygnus. Both Pelican and North America nebulae are part of the same large and complex star forming region, almost as nearby as the better-known Orion Nebula. From our vantage point, dark dust clouds (upper left) help define the Pelican's eye and long bill, while a bright front of ionized gas suggests the curved shape of the head and neck. This striking synthesized color view utilizes narrowband image data recording the emission of hydrogen and oxygen atoms in the cosmic cloud. The scene spans some 30 light-years at the estimated distance of the Pelican Nebula.

                                                                                          apod.nasa.gov/apod/ap161119.ht

                                                                                          2016 November 19 IC 5070: A Dusty Pelican in the Swan * Image Credit & Copyright: Steve Richards (Chanctonbury Observatory) Explanation: The recognizable profile of the Pelican Nebula soars nearly 2,000 light-years away in the high flying constellation Cygnus, the Swan. Also known as IC 5070, this interstellar cloud of gas and dust is appropriately found just off the "east coast" of the North America Nebula (NGC 7000), another surprisingly familiar looking emission nebula in Cygnus. Both Pelican and North America nebulae are part of the same large and complex star forming region, almost as nearby as the better-known Orion Nebula. From our vantage point, dark dust clouds (upper left) help define the Pelican's eye and long bill, while a bright front of ionized gas suggests the curved shape of the head and neck. This striking synthesized color view utilizes narrowband image data recording the emission of hydrogen and oxygen atoms in the cosmic cloud. The scene spans some 30 light-years at the estimated distance of the Pelican Nebula. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                                          Alt...2016 November 19 IC 5070: A Dusty Pelican in the Swan * Image Credit & Copyright: Steve Richards (Chanctonbury Observatory) Explanation: The recognizable profile of the Pelican Nebula soars nearly 2,000 light-years away in the high flying constellation Cygnus, the Swan. Also known as IC 5070, this interstellar cloud of gas and dust is appropriately found just off the "east coast" of the North America Nebula (NGC 7000), another surprisingly familiar looking emission nebula in Cygnus. Both Pelican and North America nebulae are part of the same large and complex star forming region, almost as nearby as the better-known Orion Nebula. From our vantage point, dark dust clouds (upper left) help define the Pelican's eye and long bill, while a bright front of ionized gas suggests the curved shape of the head and neck. This striking synthesized color view utilizes narrowband image data recording the emission of hydrogen and oxygen atoms in the cosmic cloud. The scene spans some 30 light-years at the estimated distance of the Pelican Nebula. Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U.

                                                                                            [?]grobi » 🌐
                                                                                            @grobi@defcon.social

                                                                                            2025 January 22

                                                                                            The North America Nebula
                                                                                            * Image Credit & Copyright: Dimitris Valianos

                                                                                            Explanation:
                                                                                            The North America nebula on the sky can do what the North America continent on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent, the bright part that appears as the east coast is actually a hot bed of gas, dust, and newly formed stars known as the Cygnus Wall. The featured image shows the star forming wall lit and eroded by bright young stars and partly hidden by the dark dust they have created. The part of the North America nebula (NGC 7000) shown spans about 50 light years and lies about 1,500 light years away toward the constellation of the Swan (Cygnus).

                                                                                            apod.nasa.gov/apod/ap250122.ht

                                                                                            2025 January 22 A star field is dominated by a red and blue glowing nebula. This nebula appears, to some, to have the shape of North America and so is called the North America Nebula. The North America Nebula * Image Credit & Copyright: Dimitris Valianos Explanation: The North America nebula on the sky can do what the North America continent on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent, the bright part that appears as the east coast is actually a hot bed of gas, dust, and newly formed stars known as the Cygnus Wall. The featured image shows the star forming wall lit and eroded by bright young stars and partly hidden by the dark dust they have created. The part of the North America nebula (NGC 7000) shown spans about 50 light years and lies about 1,500 light years away toward the constellation of the Swan (Cygnus). Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

                                                                                            Alt...2025 January 22 A star field is dominated by a red and blue glowing nebula. This nebula appears, to some, to have the shape of North America and so is called the North America Nebula. The North America Nebula * Image Credit & Copyright: Dimitris Valianos Explanation: The North America nebula on the sky can do what the North America continent on Earth cannot -- form stars. Specifically, in analogy to the Earth-confined continent, the bright part that appears as the east coast is actually a hot bed of gas, dust, and newly formed stars known as the Cygnus Wall. The featured image shows the star forming wall lit and eroded by bright young stars and partly hidden by the dark dust they have created. The part of the North America nebula (NGC 7000) shown spans about 50 light years and lies about 1,500 light years away toward the constellation of the Swan (Cygnus). Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Amber Straughn Specific rights apply. NASA Web Privacy, Accessibility, Notices; A service of: ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U.

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