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Space Science

A Map of the Universe, 10 Years In the Making 130

Posted by timothy
from the so-it's-gotta-be-good dept.
gabbo529 writes "Astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) have created a map of the universe called the 2MASS Redshift Survey. The astronomers put in 10 laborious years in creating the map and it is what they call the most complete 3-D map of the local universe (out to a distance of 380 million light-years) ever created. 2MASS Redshift Survey extends closer to the Galactic plane than any other map of the universe before it; the region is generally obscured by dust."
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A Map of the Universe, 10 Years In the Making

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  • So... (Score:5, Funny)

    by Kenja (541830) on Thursday May 26, 2011 @08:22PM (#36258650)
    What you're saying is its ten years out of date?
    • by Anonymous Coward on Thursday May 26, 2011 @08:29PM (#36258706)

      The map is not ten years out of date.

      It is 380 million years out of date, in places.

      Instead, it took ten years to find out how out of date it really was.

      • by erroneus (253617)

        I was going to say something similar, but you beat me to it. Yeah... time, space and the speed of light are all to be figured. For all we know, none of those stars and galaxies even exist at this moment. They could have been destroyed to make way for some sort of space highway project already. (Don't forget your towel!)

        In some respects, the idea of mapping the known universe is like mapping out a splash of water captured in super slow motion. It's all very interesting, but by the time you might be able

    • by jhoegl (638955)
      and it is on a 2d format... WTF?
      • by JWSmythe (446288)

        No, their high resolution picture is a (relatively) low result 2d single plane map. And honestly, I can't even begin to guess at the distances. I'll assume that's what the red shift color scale is, but then that indicates that the colors of the stars they represent.

        I'd assume that we (earth) is the center of the universe, as it's what we can see from here. The coordinates are nice and all, but I don't have a frame of reference to guess which direction is what.

        • I'd love too see that done in Universe Sandbox.

        • by lsamaha (2034456)
          I'd recommend all "why isn't this in 3d" posters take a look at boristhespider's response to "Observations indicate that the map must be wrong". The data "is what it is", and it does not claim to be distance data. Building a 3d model from it would make that claim, and informed people in the field apparently wouldn't be so ready to do that for good reasons.
    • by antdude (79039)

      Its what ten years out of date? :P

    • by laejoh (648921)
      All the stars are 10 lightyears closer! The universe is shrinking! We're ALL doomed I say. Doomed!
    • by gsslay (807818)

      It's rubbish. If this was any good I could zoom in down to streetlevel view.

  • If that is correct, does green mean on the same vector?

    Also, it would appear that the universe within 380 millions years was not expanding but contracting, at least it appears to have more blue to me than red.

    What would be neat is if they re-did the map with positions adjusted for the "redshift" where you could compare by toggling quickly back and forth, to get an idea of how much difference there is between what we see due to speed of light and the time for it to hit our eyes from the star, and what we bel

    • blue = closest, red = furthest, green = in between. They're color-coding distance, not red shift per se.

      • Well, not really. The press release talks about distances (hence that 380m light years bit) but the plot itself is marked up in redshifts. Then they're just colour-coding for those.

    • Also, it would appear that the universe within 380 millions years was not expanding but contracting, at least it appears to have more blue to me than red.

      Just a guess: that might be the gravitationally-bound local group. We're in for a collision with Andromeda in a few billion years!

  • by Greyfox (87712)
    Now all it needs is a microscopic dot on a microscopic dot labeled "You are here"
    • or, maybe not

    • That isn't needed since we're in the center of the universe. Or, more accurately, nothing is; any place you select has equal claim to that title. The picture isn't a 2D map, it's a projection of the sphere what we would see if we were in floating in empty space somewhere nearby, and could see redshift only instead of light. (Visual is actually not a good spectrum to see the sky, since most of what you see are particularly bright/hot stars relatively nearby. This doesn't give a very good picture of the struc
  • Give me a dataset I can import into a spacial database to query the distance between the moon and alpha centauri to the centimeter as of last tuesday adjusted for motion over duration of travel then I'll be impressed. Seriously, I want to make a time-lapse video of that helium-filled sex doll I released at the rapture party through my telescope.
  • by thelandp (632129) on Thursday May 26, 2011 @10:07PM (#36259284)

    We need to see this in Celestia!

    Does the internet accept the challenge?

    • by Trogre (513942)

      Damn, you beat me to that comment!

    • by Dasher42 (514179)

      In order to make this happen, I hope to see more volumetric effects to make those nebulae pop out. Celestia with add-ons is amazing, but it can be so much more.

    • by phme (1501991)
      Or on the soon-to-come Google Universe, I suppose...
      Then, we'll just have to wait a bit more for streetview on Epsilon Eridani c.
  • It's a little hard to tell from these images, but the videos I saw on a documentary show really well a concentration along web-like lines. Maybe neural connections are a better analogy. Pretty amazing that the universe isn't a homogenous mixture of galaxies.

    • It is isn't it? Matter almost seems to have this attractive force.... ;) But yes, it is weird and interesting, but other phenomena has exhibited similar "web like lines" as you describe it, due to an attractive pull. I do believe that usually a lack of opposing force or push (like the space vacuum for stars, i.e. pull unimpeded) helps to facilitate.

    • ....it's a tenet of cosmology (which seems more or less justified) that if you look on large enough scales it *is* a homogeneous mixture of galaxies. If it wasn't, our cosmological models would be pure baloney. (The interesting part comes when you try and actually prove that this tangled network of strings and voids and filaments and massive clumps of superclusters averages out to a homogeneous universe, given that we can't define a meaningful average in general relativity. It seems very likely, especially

    • by Hadlock (143607)

      I would love to see an animated gif of this sphere rotated so we could see the filaments. Some small amount of post processing that would elongate the dots along the filament lines would be a tremendous help.

  • I have a map of the Universe, it's actual size. It says One Megaparsec = One Megaparsec.

    Or even worse, it says One Kessel Run = Less Than Twelve Parsecs.

    • Why would a map show a "run" (course) in distance (parsecs) when that unit of measurement is obviously used in a way such as a car's 0-60 speed(but in this case distance instead of speed)?

  • Why is there a big empty space near the "equator" of the picture?
  • If the Vs get to know that map, they will locate us, and we're done!
  • To construct the map, the standard assumption that red shift is proportional to distance was made. However, a growing body of observational evidence indicates that there are further sources of red shift not related to distance. This implies that the map must be wrong since it is based on an incomplete interpretation of red shift measurements.

    For a good documentary where the mentioned growing body of evidence is being discussed by astronomers and astrophysicists see "The Universe - Cosmology Quest". A torr

    • ..... no.

      that map is in redshift space. did you not notice the colour-coding at the bottom is in redshift? they've not converted it to distances at all. the most they might have done is removed objects with redshifts 0.01 or 0.05 or something like that.

      try and look at what's going on before you sit there banging some tired old drum.

      • by Eukariote (881204)

        You are trying to make a difference where there is none on two accounts. Firstly, taking redshift and using it as a spatial dimension for a map implies a distance interpretation or, if you wish, a uni-variate spatial interpretation of redshift. An this interpretation is obviously is wrong if, as the observational evidence indicates, there are objects with high redshift co-located with objects that have much lower redshift: the mapping is then projecting two co-located objects on different parts of the map y

        • What you're doing is interpreting redshift as distance and then attacking that. In the science that will be done on this dataset then, yes, the cosmologists will employ a background model and convert the redshifts to "distances" (if you like) to do an analysis. Of course they will; that's what you have to do. If you want to apply your own pet model to it the data is freely available. Go ahead and knock yourself out. No-one's going to stop you.

          But *that plot that they put out*, I mean *that one we're talking

          • by Eukariote (881204)

            Well, no, not my interpretation, theirs. Quoting:

            "Today, astronomers unveiled the most complete 3-D map of the local universe (out to a distance of 380 million light-years) ever created."

            A press release like that implies a spatial interpretation: "map", '3-D", "distance"...

            • That's why I emphasised "the plot we are talking about", and commented that in the press release they'd interpret it in terms of a simple model for the general public.

              "But *that plot that they put out*, I mean *that one we're talking about* is in redshift space."

              "in the press release obviously they're going to simplify down for a general audience"

              They're going to use the standard model. And like it or fucking lump it, but the standard model interprets those redshifts as evidence for a universal expansion, w

        • taking redshift and using it as a spatial dimension for a map implies a distance interpretation

          Yes it does, but since they haven't done that all you have is a strawman.

    • The map is 2-D, not 3-D, the redshifts are indicated only as colors, no distance conversion has been made. All galaxies observed with a positive redshift were included, most of the dots are galaxies with redshifts under 0.02. The greatest redshifts on the map are around 0.07. This is a tiny fraction of the largest observed redshifts, less than 3%, and the volume is likely to be correspondingly small compared to the volume of the universe (something like 1/50000 of the universe's volume if the redshift-dista

  • The map [harvard.edu] seems to be almost empty at the equator.

    I'm sure there's a logical explanation, but I've no idea what it is. Anyone care to enlighten me?

    • Re: (Score:3, Informative)

      by pherth (777159)
      It is the "shadow" of our own galaxy. This map plots objects which are far out of our own galaxy. If we look into directions where there are a lot of stars in our galaxy, the chance to detect outer-galaxy objects is small as they are behind our starts.
    • by HuguesT (84078)

      This map is in galactic coordinates, this means our own galaxy runs along the equator of this map. It is also obscuring the view, hence the lack of data in this area of the map.

  • Where is the 'You are here' marker?
  • Only 380? That's a pity. An old friend that lives 380,000,006 light years away is always inviting me over but there's no way I'd find his place without a map.

    It's probably not that far as-the-crow-flies, but light takes a longer, curvy path.

  • I might suggest taking that map along if you experiment with wormhole or quantum accelerator technologies. That is only if you get lost and have any desired to return home. Then again, torch it if you think your about to be captured. After all Hawkins thinks they will be hostile when "they" get here. He also thinks there is no God. I think he suffers from "angry-cripple-syndrome" where the sufferer's point of view is tainted by his miserable existence, hence his bleak outlook.

    Anyway..hows this load into my

  • ... just in case I ever need it!
  • by Punko (784684) on Friday May 27, 2011 @07:37AM (#36261574)
    You know the universe is large, when things out to 380 LY away are referred to as "local"

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