10 ms·

Chart of the Milky Way Includes More Than 1B Stars

110 points by artsandsci 9y ago

sunsunsunsun 9y ago
Since the article seemed to neglect actually linking to the data, it is publicly available here: https://gea.esac.esa.int/archive/ https://gea.esac.esa.int/archive/
sgt101 9y ago
I think that there must be many more than 1bn though? The area of the disk is roughly 3.14^10 light years, and it must be 10K light years thick on average so 3.14^14 cubic ly... stars seem to be much more densely packed on average than 1 per cubic ly but if we assume that Sol is the measure then the nearest star is not in a 16 cubic ly volume - so we could say 3.14^13 ish stars as an estimate. So I'd be guessing many more than 300 bn stars in the galaxy? Google says 250 +/- 150 bn. I think low...
- sjcsjc 9y ago
  "... contains a representative sample of 1 percent of the Milky Way’s orbs ..."
- Brockenstein 9y ago
  You should probably read the page before commenting on the title alone...
binalpatel 9y ago
I love thinking about the sheer scale of it all. This is a billion stars of the ~200-400 billion stars in our galaxy. The Andromeda Galaxy (the closest to us) has ~1 trillion stars. There's an estimated 100 billion planets in the Milky Way alone, and who knows how many in the Andromeda galaxy. There could be another satellite somewhere in this galaxy charting space just like this and we'd just be a bright dot to them among billions of other bright dots.
- mkempe 9y ago
  Last time I looked into this the current estimate is that there are on average 10 planets per star, so we have 1-4 trillion planets in our galaxy, and there are 10 trillion planets in Andromeda. The Universe is teeming with galaxies, which are teeming with planets. Given what we know now it is likely that they are teeming with life (organisms in a process of self-sustaining and self-generated action) as well.
  - DmenshunlAnlsis 9y ago
    The majority of those planets are unsuited to anything we can imagine being alive, or only suitable for very simple unicellular life. Most of those plants are gas giants, or blazing hot gas giants. Some are rocky, but many of those are in orbits like Mercury, which would alternately bake and freeze them. Of course, part of the reason for this might be our detection methods, but as of now, we’re not finding. I hope like Earth, Venus, or Mars, while we find a lot of Jupiter’s. Maybe we’ll disocver that something like bacteria is ubiquitous, but that doesn’t imply much for our prospects of finding intelligent life. For all that we know life is common, but multicellular life is incredibly rare, or maybe it isn’t rare, but intelligent life is.
    - dugluak 9y ago
      Wondering if giants like UY Scuti have planets and how big.
      - mkempe 9y ago
        Red supergiants are necessarily no more than about 25 million years old; they keep ejecting a lot of material, forming nebulae; and then they end as supernovae. So, unlikely to have sufficient time and relative calm to form and maintain planets.
    - binalpatel 9y ago
      There's this great article I came across a few weeks ago: https://www.theatlantic.com/science/archive/2018/03/human-existence-will-look-more-miraculous-the-longer-we-survive/554513/ https://www.theatlantic.com/science/archive/2018/03/human-ex... About how we may expect life to be more prevalent than it is because our own existence is so miraculous. Though the other side is - if the universe is so large, with so many planets, then there may be a chance that there's life out there that's just as incredibly lucky as us.
truculation 9y ago
Superb stuff. On a more mundane level I hope we'll soon also have a chart of all the asteroids in our solar system (to the most realistic extent possible).
- txsh 9y ago
  It’s not mundane to me when you consider how much mineral wealth is just out of reach.
  - m0skit0 9y ago
    I guess he implied mundane on a scale level :)
- bburns_km 9y ago
  Here's a video showing the discovery of 600,000 asteroids in the inner solar system - https://www.youtube.com/watch?v=2k2vkLEE4ko https://www.youtube.com/watch?v=2k2vkLEE4ko
  - truculation 9y ago
    Thanks! Took me a minute to work out which planet was which (Jupiter being the one just outside the 'belt').
baxtr 9y ago
It makes me sooo sad that (whoever) introduced this stupid light speed limit so we can’t visit those places. Ever. Maybe in the next reality.
- ldargin 9y ago
  Our telescopes and other instruments are getting more powerful. All we have to do is look...
  - CiaranMcNulty 9y ago
    They are similarly limited by light speed (in the other direction)
  - magduf 9y ago
    That's not that useful. It's great for looking back in time to see the origins of the universe, but if you want to communicate with someone on a planet 100 light-years away, that's a 200-year round-trip latency. And telescopes will likely never be powerful enough to see, for instance, the actual inhabitants of another planet (we'd be lucky if we could see some gigantic Death Star-sized space station optically).
    - trhway 9y ago
      >And telescopes will likely never be powerful enough to see, for instance, the actual inhabitants of another planet (we'd be lucky if we could see some gigantic Death Star-sized space station optically). gravitational lensing by Sun, just need to put the telescope at least 550 AU from the Sun. https://www.airspacemag.com/daily-planet/ultimate-space-telescope-would-use-sun-lens-180962499/ https://www.airspacemag.com/daily-planet/ultimate-space-tele... "And using the Sun as a lens would result in much greater magnification. Instead of a single pixel or two, astronomers would get images of 1,000 x 1,000 pixels from exoplanets 30 parsecs, or about 100 light years, away. That translates to a resolution of about 10 kilometers on the planet’s surface, better than what the Hubble Space Telescope can see on Mars, which would allow us to make out continents and other surface features." To the GGP point of light speed limit - that is only true for static fixed spacetime. The spacetime expansion/contraction doesn't seem to have that limit (this is how we have far-far galaxies receding from us at the speeds higher than c). Just an issue of engineering that into a practical drive ...
twic 9y ago
There's an incredible decade-old map that shows space around the centre of Earth on a logarithmic scale - it's detailed enough to show the core, mantle, and crust at the bottom, and the Great Walls at the top: https://www.astro.princeton.edu/universe/ https://www.astro.princeton.edu/universe/ I finally got round to printing a two metre tall version of this to hang in my hall a couple of weeks ago!
jason_slack 9y ago
This may sound odd, but does anyone know of a public dataset that provides the positions of stars and their relationship to other stars? I'd be curious to see this type of data.

110 points by artsandsci 9y ago

Since the article seemed to neglect actually linking to the data, it is publicly available here: https://gea.esac.esa.int/archive/ https://gea.esac.esa.int/archive/

sgt101 9y ago

I think that there must be many more than 1bn though? The area of the disk is roughly 3.14^10 light years, and it must be 10K light years thick on average so 3.14^14 cubic ly... stars seem to be much more densely packed on average than 1 per cubic ly but if we assume that Sol is the measure then the nearest star is not in a 16 cubic ly volume - so we could say 3.14^13 ish stars as an estimate. So I'd be guessing many more than 300 bn stars in the galaxy? Google says 250 +/- 150 bn. I think low...

sjcsjc 9y ago
"... contains a representative sample of 1 percent of the Milky Way’s orbs ..."
Brockenstein 9y ago
You should probably read the page before commenting on the title alone...

binalpatel 9y ago

I love thinking about the sheer scale of it all. This is a billion stars of the ~200-400 billion stars in our galaxy. The Andromeda Galaxy (the closest to us) has ~1 trillion stars. There's an estimated 100 billion planets in the Milky Way alone, and who knows how many in the Andromeda galaxy. There could be another satellite somewhere in this galaxy charting space just like this and we'd just be a bright dot to them among billions of other bright dots.

mkempe 9y ago
Last time I looked into this the current estimate is that there are on average 10 planets per star, so we have 1-4 trillion planets in our galaxy, and there are 10 trillion planets in Andromeda. The Universe is teeming with galaxies, which are teeming with planets. Given what we know now it is likely that they are teeming with life (organisms in a process of self-sustaining and self-generated action) as well.
- DmenshunlAnlsis 9y ago
  The majority of those planets are unsuited to anything we can imagine being alive, or only suitable for very simple unicellular life. Most of those plants are gas giants, or blazing hot gas giants. Some are rocky, but many of those are in orbits like Mercury, which would alternately bake and freeze them. Of course, part of the reason for this might be our detection methods, but as of now, we’re not finding. I hope like Earth, Venus, or Mars, while we find a lot of Jupiter’s. Maybe we’ll disocver that something like bacteria is ubiquitous, but that doesn’t imply much for our prospects of finding intelligent life. For all that we know life is common, but multicellular life is incredibly rare, or maybe it isn’t rare, but intelligent life is.
  - dugluak 9y ago
    Wondering if giants like UY Scuti have planets and how big.
    - mkempe 9y ago
      Red supergiants are necessarily no more than about 25 million years old; they keep ejecting a lot of material, forming nebulae; and then they end as supernovae. So, unlikely to have sufficient time and relative calm to form and maintain planets.
  - binalpatel 9y ago
    There's this great article I came across a few weeks ago: https://www.theatlantic.com/science/archive/2018/03/human-existence-will-look-more-miraculous-the-longer-we-survive/554513/ https://www.theatlantic.com/science/archive/2018/03/human-ex... About how we may expect life to be more prevalent than it is because our own existence is so miraculous. Though the other side is - if the universe is so large, with so many planets, then there may be a chance that there's life out there that's just as incredibly lucky as us.

truculation 9y ago

Superb stuff. On a more mundane level I hope we'll soon also have a chart of all the asteroids in our solar system (to the most realistic extent possible).

txsh 9y ago
It’s not mundane to me when you consider how much mineral wealth is just out of reach.
- m0skit0 9y ago
  I guess he implied mundane on a scale level :)
bburns_km 9y ago
Here's a video showing the discovery of 600,000 asteroids in the inner solar system - https://www.youtube.com/watch?v=2k2vkLEE4ko https://www.youtube.com/watch?v=2k2vkLEE4ko
- truculation 9y ago
  Thanks! Took me a minute to work out which planet was which (Jupiter being the one just outside the 'belt').

baxtr 9y ago

It makes me sooo sad that (whoever) introduced this stupid light speed limit so we can’t visit those places. Ever. Maybe in the next reality.

ldargin 9y ago
Our telescopes and other instruments are getting more powerful. All we have to do is look...
- CiaranMcNulty 9y ago
  They are similarly limited by light speed (in the other direction)
- magduf 9y ago
  That's not that useful. It's great for looking back in time to see the origins of the universe, but if you want to communicate with someone on a planet 100 light-years away, that's a 200-year round-trip latency. And telescopes will likely never be powerful enough to see, for instance, the actual inhabitants of another planet (we'd be lucky if we could see some gigantic Death Star-sized space station optically).
  - trhway 9y ago
    >And telescopes will likely never be powerful enough to see, for instance, the actual inhabitants of another planet (we'd be lucky if we could see some gigantic Death Star-sized space station optically). gravitational lensing by Sun, just need to put the telescope at least 550 AU from the Sun. https://www.airspacemag.com/daily-planet/ultimate-space-telescope-would-use-sun-lens-180962499/ https://www.airspacemag.com/daily-planet/ultimate-space-tele... "And using the Sun as a lens would result in much greater magnification. Instead of a single pixel or two, astronomers would get images of 1,000 x 1,000 pixels from exoplanets 30 parsecs, or about 100 light years, away. That translates to a resolution of about 10 kilometers on the planet’s surface, better than what the Hubble Space Telescope can see on Mars, which would allow us to make out continents and other surface features." To the GGP point of light speed limit - that is only true for static fixed spacetime. The spacetime expansion/contraction doesn't seem to have that limit (this is how we have far-far galaxies receding from us at the speeds higher than c). Just an issue of engineering that into a practical drive ...

twic 9y ago

There's an incredible decade-old map that shows space around the centre of Earth on a logarithmic scale - it's detailed enough to show the core, mantle, and crust at the bottom, and the Great Walls at the top: https://www.astro.princeton.edu/universe/ https://www.astro.princeton.edu/universe/ I finally got round to printing a two metre tall version of this to hang in my hall a couple of weeks ago!

jason_slack 9y ago

This may sound odd, but does anyone know of a public dataset that provides the positions of stars and their relationship to other stars? I'd be curious to see this type of data.