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Direct link to some very very nice images and animations: https://www.esa.int/Science_Exploration/Space_Science/Gaia https://www.esa.int/Science_Exploration/Spa

Direct link to some very very nice images and animations: https://www.esa.int/Science_Exploration/Space_Science/Gaia https://www.esa.int/Science_Exploration/Space_Science/Gaia Two of my favorites: https://www.esa.int/ESA_Multimedia/Images/2025/The_best_Milky_Way_map_by_Gaia https://www.esa.int/ESA_Multimedia/Images/2025/The_best_Milk... https://www.esa.int/ESA_Multimedia/Images/2025/01/The_best_Milky_Way_map_by_Gaia_edge-on https://www.esa.int/ESA_Multimedia/Images/2025/01/The_best_M...

dylan604 2y ago
I get how Gaia could make the best edge on image, but how could Gaia (or anything man made) get the the "best" face on image?
- iAmAPencilYo 2y ago
  All of these are "Artist's Impressions". My best guess is they run a simulation based on the data from the spacecraft and then can pan the camera around as they see fit
  - BizarroLand 2y ago
    From the page: [Image Description: A model image of what our home galaxy, the Milky Way, might look like edge-on, against a pitch-black backdrop. The Milky Way’s disc appears in the centre of the image, as a thin, dark-brown line spanning from left to right, with the hint of a wave in it. The line appears to be etched into a thin glowing layer of silver sand, that makes it look as if it was drawn with a coloured pencil on coarse paper. The bulge of the galaxy sits like a glowing, see-through pearl in the shape of a sphere in the centre of this brown line.]
    - hahajk 2y ago
      That's an AI produced accessibility description so I thought it seemed wrong. But more directly from the article text: This is a new artist’s impression of our galaxy, the Milky Way, based on data from ESA’s Gaia space telescope.
      - Cthulhu_ 2y ago
        Is it AI produced (if so, do they communicate it somewhere?) or do you believe it is?
  - dylan604 2y ago
    "The best Milky Way map, by Gaia (edge-on)" The "by Gaia" implies the opposite to me. Unless the "artist's impressions" are from someone named Gaia???
    - Cthulhu_ 2y ago
      "This is a new artist’s impression of our galaxy, the Milky Way, based on data from ESA’s Gaia space telescope." I'm sure you know of headlines vs details; when it comes down to it, space science relies on marketing to get some funding and interest in it, and using 100% accurate headlines is not good marketing.
  - Keysh 2y ago
    The face-on galaxy image is credited to Stefan Payne-Wardenaar (https://stefanpw.myportfolio.com/home https://stefanpw.myportfolio.com/home), whose Twitter and Bluesky bios say, "I make astronomy visualizations in Blender."
- goodcanadian 2y ago
  The whole purpose of Gaia is to precisely measure the position of stars (and other objects). Once positions are known, a 3D model can be built. But how are the distances measured? The answer is parallax, essentially triangulation. You look for very small changes of position against the background sky. You use the width of the earth's orbit as the baseline and measure at different times of the year.
- sbierwagen 2y ago
  It can't. The galaxy is assumed to be roughly symmetrical, and they fill in the missing data with what we can see on our side of the galaxy. It's "best" in the sense that it's the most accurate fiction, I suppose. Gaia is good to about 13,000 light years: https://en.wikipedia.org/wiki/File:Galaxymap.com,_map_12000_parsecs_(2022).png https://en.wikipedia.org/wiki/File:Galaxymap.com,_map_12000_... The Milky Way is maybe 100,000 light years in diameter. So we're only getting good distance readings on a small fraction, and nothing behind the central bulge of our galaxy. The first won't improve until we send an astrometry telescope way outside the orbit of the Earth, for better baselines, and the second is going to need a telescope sent 10,000 light years out of the galactic ecliptic.
  - thrance 2y ago
    We can infer the general distribution of mass on the other side of the galaxy from observing the trajectory of stars, can't we?
    - sbierwagen 2y ago
      It takes 230 million years for the Sun to make one full orbit around the Milky Way.
      - gunian 2y ago
        huh? how can sun orbit the milky way if it is within the milky way
        dylan604 2y ago
        Around the center of the Milky Way. The sun orbits the center just like the planets orbit the sun.
        gunian 2y ago
        is there some sort of gravitational body in the middle that makes everything orbit in galaxies? it must be massive right

dylan604 2y ago

I get how Gaia could make the best edge on image, but how could Gaia (or anything man made) get the the "best" face on image?

iAmAPencilYo 2y ago
All of these are "Artist's Impressions". My best guess is they run a simulation based on the data from the spacecraft and then can pan the camera around as they see fit
- BizarroLand 2y ago
  From the page: [Image Description: A model image of what our home galaxy, the Milky Way, might look like edge-on, against a pitch-black backdrop. The Milky Way’s disc appears in the centre of the image, as a thin, dark-brown line spanning from left to right, with the hint of a wave in it. The line appears to be etched into a thin glowing layer of silver sand, that makes it look as if it was drawn with a coloured pencil on coarse paper. The bulge of the galaxy sits like a glowing, see-through pearl in the shape of a sphere in the centre of this brown line.]
  - hahajk 2y ago
    That's an AI produced accessibility description so I thought it seemed wrong. But more directly from the article text: This is a new artist’s impression of our galaxy, the Milky Way, based on data from ESA’s Gaia space telescope.
    - Cthulhu_ 2y ago
      Is it AI produced (if so, do they communicate it somewhere?) or do you believe it is?
- dylan604 2y ago
  "The best Milky Way map, by Gaia (edge-on)" The "by Gaia" implies the opposite to me. Unless the "artist's impressions" are from someone named Gaia???
  - Cthulhu_ 2y ago
    "This is a new artist’s impression of our galaxy, the Milky Way, based on data from ESA’s Gaia space telescope." I'm sure you know of headlines vs details; when it comes down to it, space science relies on marketing to get some funding and interest in it, and using 100% accurate headlines is not good marketing.
- Keysh 2y ago
  The face-on galaxy image is credited to Stefan Payne-Wardenaar (https://stefanpw.myportfolio.com/home https://stefanpw.myportfolio.com/home), whose Twitter and Bluesky bios say, "I make astronomy visualizations in Blender."
goodcanadian 2y ago
The whole purpose of Gaia is to precisely measure the position of stars (and other objects). Once positions are known, a 3D model can be built. But how are the distances measured? The answer is parallax, essentially triangulation. You look for very small changes of position against the background sky. You use the width of the earth's orbit as the baseline and measure at different times of the year.
sbierwagen 2y ago
It can't. The galaxy is assumed to be roughly symmetrical, and they fill in the missing data with what we can see on our side of the galaxy. It's "best" in the sense that it's the most accurate fiction, I suppose. Gaia is good to about 13,000 light years: https://en.wikipedia.org/wiki/File:Galaxymap.com,_map_12000_parsecs_(2022).png https://en.wikipedia.org/wiki/File:Galaxymap.com,_map_12000_... The Milky Way is maybe 100,000 light years in diameter. So we're only getting good distance readings on a small fraction, and nothing behind the central bulge of our galaxy. The first won't improve until we send an astrometry telescope way outside the orbit of the Earth, for better baselines, and the second is going to need a telescope sent 10,000 light years out of the galactic ecliptic.
- thrance 2y ago
  We can infer the general distribution of mass on the other side of the galaxy from observing the trajectory of stars, can't we?
  - sbierwagen 2y ago
    It takes 230 million years for the Sun to make one full orbit around the Milky Way.
    - gunian 2y ago
      huh? how can sun orbit the milky way if it is within the milky way
      - dylan604 2y ago
        Around the center of the Milky Way. The sun orbits the center just like the planets orbit the sun.
        gunian 2y ago
        is there some sort of gravitational body in the middle that makes everything orbit in galaxies? it must be massive right