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A Map of the Universe, 10 Years In the Making

timothy posted more than 3 years ago | from the so-it's-gotta-be-good dept.

Space 130

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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So... (4, Funny)

Kenja (541830) | more than 3 years ago | (#36258650)

What you're saying is its ten years out of date?

Re:So...not ten years out of date (5, Insightful)

Anonymous Coward | more than 3 years ago | (#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The map is not ten years out of date.

It is 380 million years out of date, in places.

Instead, it took ten years to find out how out of date it really was.

Re:So...not ten years out of date (0)

Anonymous Coward | more than 3 years ago | (#36260938)

380 million and 10, I think you'll find.

Re:So... (0)

Anonymous Coward | more than 3 years ago | (#36258734)

Actually more than 380 million years too late, since those astral bodies would have moved for quite a distance when their light reaches earth :D

Re:So... (1)

JWSmythe (446288) | more than 3 years ago | (#36259874)

  How much could the universe have changed in 380 million years.

    Oh... ya... An awful lot. This [youtube.com] is what was observed from a single location, looking at a very small portion of the sky (approx 1/10,000), looking for a specific type of supernova. In 3 years, in 1/10,000th of the sky, they identified 241 new supernovas.

    I know you can't extrapolate that tiny sample set out to the whole period. That would be far too easy. (241 * 10000) * 380 million years. Nope, that'd be way too easy. And ya, planets, stars, and entire galaxies come and go. There's a whole new universe out there to explore. Oh. We don't have space travel.

   

Re:So... (0)

Anonymous Coward | more than 3 years ago | (#36260540)

Oh... ya... An awful lot. This [youtube.com] is what was observed from a single location, looking at a very small portion of the sky (approx 1/10,000), looking for a specific type of supernova. In 3 years, in 1/10,000th of the sky, they identified 241 new supernovas.

How cool, that's just like the screen saver in Norton Commander for DOS!

Re:So... (1)

JWSmythe (446288) | more than 3 years ago | (#36260924)

    I wouldn't know. I never used NC. I was always very happy with my copy of DesqView, with 3 windows running my BBS, and the fourth for whatever I wanted to do. Oh, the good old days. :)

Re:So... (0)

jhoegl (638955) | more than 3 years ago | (#36258736)

and it is on a 2d format... WTF?

Re:So... (2)

JWSmythe (446288) | more than 3 years ago | (#36258896)

    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.

    It would have been nice if they used a 3d engine of some sort, and plotted the stars in that. Or made the information available so someone else could do it. With just the raw data (3d coordinate, direction of motion, direction of expansion, color (RGB would be fine for most of us), and observed size, there'd probably be dozens of 3d representations of it within a week or two, just from the folks on here.

    At least there's at least something here [harvard.edu]

Re:So... (1)

sortius_nod (1080919) | more than 3 years ago | (#36259186)

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

Re:So... (0)

Anonymous Coward | more than 3 years ago | (#36259238)

the co-ordinates on the axes are relative to the galactic plane, presumably with 0,0 indicating the direction to galactic center.
the redshift can be interpreted as a distance from us (at center), not star colors.
google: "redshift distance" and you'll find various conversions.

Re:So... (1)

JWSmythe (446288) | more than 3 years ago | (#36259542)

    Right, but a mess of colors on a 2d image then doesn't give us an indication of what color the planets are, nor can we easily identify distance.

    They have the source data that generated the image. There's no way any of us (ok, most of us) are going to try to reverse engineer the list from the image. Even if we did reverse engineer direction and distance, that still doesn't give us indication of motion in the galaxies or around other bodies, but I guess we could at least find the outward vector from what we perceive as the center of the universe.

Re:So... (1)

boristhespider (1678416) | more than 3 years ago | (#36260262)

That plot is absolutely rubbish. I do know what redshift is, I do know the coordinates they're using on the plot, and I even understand why they might want to do a 2D plot (because that's basically we see from Earth; everything is projected onto the celestial sphere; and if you converted to distances you'd be making a lot of model-specific assumptions). But that plot is still absolutely rubbish. Surely they can do better than that? At the very least they could do a 3D plot in redshift-space. That's not hard. Sloan and 2dF did big wedges in redshift space ten years ago.

Also, "a mess of colors on a 2d image then doesn't give us an indication of what color the planets are". Planets? These aren't even *stars* they're looking at, they're entire galaxies. Each individual point will be a galaxy at least as big as our own, or perhaps quite a few galaxies as big as our own.

And can you imagine how messy the plot would be if they gave us some clue of the galaxy motions? It's a horrible mess as it is. If they added a bunch of vectors showing the peculiar velocity (a conversion, by the way, that *also* involves a lot of model-specific assumptions, since the bulk of the galaxy motion is coming from the universal expansion, which has to be subtracted) then it would look like a child's scribble.

Re:So... (1)

JWSmythe (446288) | more than 3 years ago | (#36260892)

Planets? These aren't even *stars* they're looking at, they're entire galaxies

Ya, I just re-read what I wrote. I can't believe I wrote planets. I frequently am talking to my girlfriend while I'm writing, so sometimes I type what I'm saying rather than what I'm thinking. :)

Most of what we're seeing are galaxies, supernovas, and even galactic clusters.

And can you imagine how messy the plot would be if they gave us some clue of the galaxy motions? It's a horrible mess as it is. If they added a bunch of vectors showing the peculiar velocity (a conversion, by the way, that *also* involves a lot of model-specific assumptions, since the bulk of the galaxy motion is coming from the universal expansion, which has to be subtracted) then it would look like a child's scribble.

I wasn't suggesting that they show the motion in the plot. It would give the ability to add some fluidity to a 3d map. Not only could we move among the "stars" (galaxies, as you so properly noted), but you could set an accelerated timetable to be able to move among them in their motion. I do realize that we'd be talking about something on the scale of a minute equals a million years or more, and just because we know two objects are heading towards each other doesn't really mean much as our perception from here is just a dot in the sky, and those objects may be light years apart, moving on non-intersecting paths. It will still be far more interesting, and let our imaginations wander than "look, here's a 2d picture of a 3d rendering, which isn't actually 3d."

    Consider how many people "travel" along Google Earth, just to have the idea of the experience of traveling over vast distances. I've gone cruising up along the Asian Pacific coast just to see what's there. I've found interesting places on it, and have sent the links to some ex-military intelligence friends of mine so we could have interesting discussions on what it could be. I found a fleet of submarines off of North Korea, and nuclear power stations in both North Korea and China. They weren't marked as "Here's a nuclear power plant". Actually, they weren't marked as anything at all being there. There are some signatures you can look for in the photos which make their real purpose pretty obvious.

    People have a lot of curiosity, and that includes traveling through places that they can't. I doubt China nor North Korea would ever let me fly along their borders or hundreds of miles inland arbitrarily to look at things that they'd rather keep secret. But the secrets aren't just in far away places. For example, someone told me a story about being at a military base on the Aleution chain. This was back in the Vietnam era. The whole purpose of that base was to watch a Russian base on the horizon. So I said to myself "Hey, lets see if we can find them." Both bases appear to be almost totally abandon, but I found some small airports near by, and the FAA had live streaming weather cameras up. With public weather information, and looking through the cameras, it gave me a sense of being there. Since it was about 90 degrees here, it gave me chills almost immersing myself in as much information as I could find about that place. Sometimes you see things you are pretty sure you didn't, like this [google.com] . Hmmm, looking at this one more, there's an awful lot of man made stuff out there, including 3 airports, and some recent tire tracks in the snow. Well, as recent as the last images were taken, but still.... It makes you wonder what you'd find if you went there to visit. It's not really recommended though, since the DOE considers it hot, and the nearest help when you realize your freezing your ass off in the middle of nowhere, is NAS Attu.

Re:So... (1)

boristhespider (1678416) | more than 3 years ago | (#36261206)

Oh I totally agree with you. At the least they could have released a 3D chart with galactic coordinates and redshift as the axes, even if they didn't convert to distances -- or converted to distances and printed the caveats about that conversion being model-dependent. It woudl really help visualisation. I imagine it'll happen soon though; it didn't take long for someone to import the SDSS data (release 1 or release 3, last time I checked, unless it was actually 2dF) into Celestia and someone will do the same with this. Then we can go flying around through it -- and it really helps emphasise the filamentary nature of the cosmos when you do that, too.

Re:So... (1)

antdude (79039) | more than 3 years ago | (#36259766)

Its what ten years out of date? :P

Re:So... (1)

laejoh (648921) | more than 3 years ago | (#36260542)

All the stars are 10 lightyears closer! The universe is shrinking! We're ALL doomed I say. Doomed!

Re:So... (1)

gsslay (807818) | more than 3 years ago | (#36260668)

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

EVE (0)

Anonymous Coward | more than 3 years ago | (#36258688)

Empire space is bigger than I thought.

Star trek! (0)

rahst12 (1395987) | more than 3 years ago | (#36258710)

This is awesome!! Here we go astrophysics lab in star trek!!

Re:Star trek! (1)

belthize (990217) | more than 3 years ago | (#36259522)

Kind of like long range scans playing Star Trek on a line printer.

Asshats. Where's the 3D? (-1, Flamebait)

VortexCortex (1117377) | more than 3 years ago | (#36258796)

I mean, for fuck's sake, give me the vector coordinates and I'll make a shit load of files for everyone who wants to view the data in actual 3D -- .blend, .obj, .3ds and several levels for Alien Arena. Hell I have a script that already does this for point clouds (esp. for Kinect) that I can adapt in about 10 minuets. WAD?! (where's all the data?)

Oh sure YOU created a 3D map -- please, no -- you measured the 3D coordinates. Give them to us so we can actually see it -- Oh, I forgot, the purpose of today's research agencies and universities is to charge exorbitant fees for basic knowledge.

The bullshit 3D movies they'll come out with will pale in comparison to the crowd soured galaxy naming/classifying cross reference websites we could make -- if only they weren't Data Nazis. Of course we could suggest more red-shift surveys based on interesting imagines obtained from the Hubble and other telescopes -- Imagine being able to actually map the galaxy by virtually flying around in it, and having beautiful annotated pictures and comments appearing as you approach select parts...

I could reverse engineer their bullshit 2D map, but that would be a waste of time since they have the 3D coordinates they used to plot the map.

Knowledge like this is only of value if it's made free (as in freedom).

Data links (via Coral Cache) (0)

Anonymous Coward | more than 3 years ago | (#36258914)

I think these are the (Coral Cache 'd) download links for the data. Please don't abuse them directly (i.e. go through Coral Cache):

The 6dF Galaxy Survey Redshift Catalogue Data Release 3 (final) catalogue file ... (124703 entries in all)
http://www-wfau.roe.ac.uk.nyud.net/6dFGS/6dFGSzDR3.txt.gz

a comma-separated file the table of spectral observations, a subset of parameters is provided
http://www-wfau.roe.ac.uk.nyud.net/6dFGS/spec_dr3.csv.gz .. and the Coral cached main page for the database:
http://www-wfau.roe.ac.uk.nyud.net/6dFGS/

Re:Data links (via Coral Cache) (0)

Anonymous Coward | more than 3 years ago | (#36258966)

(AC replying to self)

Sorry... I think the above is just one of 2MASS's sources (amongst several). Also, it's in red-shift form (?) which isn't immediately useful to most.

Re:Data links (via Coral Cache) (1)

jd (1658) | more than 3 years ago | (#36258996)

2MASS publish their full catalogue on their FTP server. It's painful to download, even on broadband.

Re:Data links (via Coral Cache) (0)

Anonymous Coward | more than 3 years ago | (#36259104)

I've found the FTP site now (thanks google..).

I may be mistaken (as I was before..), but I think they have data on 470,992,970 perceived objects. I suppose that could be a lot of data, depending on encoding and level of detail.

Re:Data links (via Coral Cache) (1)

boristhespider (1678416) | more than 3 years ago | (#36260282)

It's a lot more useful to be in redshift space than it would be in "real" space. To swap it to real space you have to make a lot of assumptions about the nature of the universe, and you get out something that may or may not actually correspond to the actual distribution. Redshift space is distorted by other effects, particularly for galaxies nearby where the Hubble flow is weak and peculiar motions strong (the extreme example being the Andromeda galaxy with its strong blue-shift given that it's flying straight at us looking for a barney) but it's still what we actually see.

It's always possible anyway to draw a 3D plot with galactic coordinates and then redshift as your third axis. That's how I'd recommend it.

Re:Data links (via Coral Cache) (0)

Anonymous Coward | more than 3 years ago | (#36258974)

Amazing. 10 years of scientific data takes up just 9.3 MB.

Oh look, my torrent for the 25 GB Blu-ray rip of Backdoor Sluts 9 just finished downloading.

Re:Data links (via Coral Cache) (1)

buchner.johannes (1139593) | more than 3 years ago | (#36259732)

So for the southern hemisphere you want to fetch the 6dF catalogue, for the northern, zcat.
The best to get those is using vizier, for instance as two tab-separated file.
zcat -- http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=VII/193 [u-strasbg.fr] -- select zcat -- select column vh only, this is recessional velocity in km/s
6dF -- http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=VII/249 [u-strasbg.fr] -- select spectra -- select column z only, this is redshift

You will find conversions between distance, velocity and redshift z in http://en.wikipedia.org/wiki/Redshift [wikipedia.org]
The first 2 columns will refer to the RA/Dec. You can plot these directly, or optionally convert into some other coordinate system (e.g. galactic). http://en.wikipedia.org/wiki/Celestial_coordinate_system [wikipedia.org]

Re:Asshats. Where's the 3D? (0)

Anonymous Coward | more than 3 years ago | (#36258942)

WAD?!

They released it as a DOOM map?

Re:Asshats. Where's the 3D? (1)

jd (1658) | more than 3 years ago | (#36259008)

Some of those stars must have monsters wielding plasma rifles, right?

Re:Asshats. Where's the 3D? (1)

FrootLoops (1817694) | more than 3 years ago | (#36258962)

Supposing the data hasn't been put online somewhere (and from another comment to your post, it looks like it has), I'm certain the researches themselves could be contacted for the data you seek. Publicly funded research usually requires data release upon request.

Re:Asshats. Where's the 3D? (1)

Nyder (754090) | more than 3 years ago | (#36259004)

I mean, for fuck's sake, give me the vector coordinates and I'll make a shit load of files for everyone who wants to view the data in actual 3D -- .blend, .obj, .3ds and several levels for Alien Arena. Hell I have a script that already does this for point clouds (esp. for Kinect) that I can adapt in about 10 minuets. WAD?! (where's all the data?)

Oh sure YOU created a 3D map -- please, no -- you measured the 3D coordinates. Give them to us so we can actually see it -- Oh, I forgot, the purpose of today's research agencies and universities is to charge exorbitant fees for basic knowledge.

The bullshit 3D movies they'll come out with will pale in comparison to the crowd soured galaxy naming/classifying cross reference websites we could make -- if only they weren't Data Nazis. Of course we could suggest more red-shift surveys based on interesting imagines obtained from the Hubble and other telescopes -- Imagine being able to actually map the galaxy by virtually flying around in it, and having beautiful annotated pictures and comments appearing as you approach select parts...

I could reverse engineer their bullshit 2D map, but that would be a waste of time since they have the 3D coordinates they used to plot the map.

Knowledge like this is only of value if it's made free (as in freedom).

word.

Re:Asshats. Where's the 3D? (0)

Anonymous Coward | more than 3 years ago | (#36259050)

http://www.shatters.net/celestia/

Re:Asshats. Where's the 3D? (0)

Anonymous Coward | more than 3 years ago | (#36260628)

That is cool, but I want webGL :)

Re:Asshats. Where's the 3D? (5, Informative)

PvtVoid (1252388) | more than 3 years ago | (#36259208)

Here you go [caltech.edu] . Dipshit.

Re:Asshats. Where's the 3D? (0)

Anonymous Coward | more than 3 years ago | (#36259494)

+1 on this. I swear all these video games / tv are making people angry, impatient and just mean spirited.

Re:Asshats. Where's the 3D? (0)

Anonymous Coward | more than 3 years ago | (#36260588)

Caffeine combined with a lack of exercise and sunlight is lethal for your personality.

Re:Asshats. Where's the 3D? (0)

Anonymous Coward | more than 3 years ago | (#36260922)

Besides, his mom told him to clean the basement.

Re:Asshats. Where's the 3D? (0)

Anonymous Coward | more than 3 years ago | (#36259660)

After clicking that link, it's still a bit of a trudge for a non-expert in astronomy to find a good/best set of point data (such as might be useful to someone expert in graphics and/or 3D.. as I'm sure there are many here). Has anyone figured this out?

And of course I'm in agreement that the grandparent was excessively rude (I can sympathize in the respect that to us, it is frustrating that the most useful data is often either not shared or is hidden deeply away as an aside. It really should be shared most prominently, as it would affect the public in a much greater way after a short time as the masses find interesting ways to process the data.. but there is no excuse for that sort of behavior).

GP misunderstands problem, but it's real (1)

Anonymous Coward | more than 3 years ago | (#36259718)

While the GP misdiagnoses it, there is a problem.

Consider:

() The scientific literature is still far from being all open access.
Astronomy is great, with its preprint culture. Education research is surprisingly among the worst. "Oh, you wish to {teach your child, edit wikipedia, blog about} _physics_? That will be $$ per year or $$ per article here you wish to skim. Oh, math too? That will be..." Also, people are more likely to hear about papers in prestige journals, which are more likely to be paywalled. And as "research paper blogging" increases, and more people look at literature, more encounter the problem. Which all sucks to a degree easily forgotten if you have an "in" through the wall.

() At the time news stories happen, the data is often still being mined, and thus not easily available. So the one time people widely hear about a project, they can't get at the data. And no one ever invests the time to derive a mangled dataset, useless for science, but useful for curiosity or science education.

But there are more puzzling problems. What's going on in the following case?

() There is much institutional and community interest in outreach regarding climate change, evolution, and anthropogenic extinction. Understanding deep time is important for all these (there's even literature on that). So you'd think there would be, for instance, interactive javascript paleoglobes everywhere. But no.

The data exists (eg, https://sites.google.com/a/upr.edu/planetary-habitability-laboratory-upra/projects/visual-paleo-earth [google.com] ). Doing javascript globes has gotten so easy it's used for throw-away demos (eg, http://mrdoob.github.com/three.js/examples/canvas_geometry_earth.html [github.com] ). So how many more years will it be before those 1+1 get combined into a desperately needed 2? And why have several years passed already?

() There are even simpler examples of this puzzle. There aren't any good CC pictures of blood on the web. Images showing blood is a concentrated slurry of red blood cells. The need is known - the WP page has a blood smear, a three cell micrograph, and says "still looking for more good images". The consequences are known - youtube has some science misunderstanding interview videos of 'students think blood is purple, or half red and half blue' (which I can't find just now). The data exists - the folks doing blood fluid dynamics simulation have some wonderful videos and images. Mostly not online. None with an open license. Why? Well, that just didn't occur to them. And no one asks.

Perhaps it's a failure of communication? Or of vision? The lack of anyone tasked with making this stuff happen? And the default of mob sourcing it not yet being effective?

Science education content is pervasively wretched... and it's not clear why we're still letting it be so.

Mitchell N Charity
(interested in "extreme-effort" descriptive content for K-grad science and engineering education)

Re:GP misunderstands problem, but it's real (1)

uglyMood (322284) | more than 3 years ago | (#36259834)

I'd be more impressed with the javascript globe if it were rotating in the right direction. Unless it's representing the alternate Earth from 'The Green Berets', of course.

Re:Asshats. Where's the 3D? (-1)

Anonymous Coward | more than 3 years ago | (#36259282)

Fuck you nigger.

callling this a map of the universe (0)

Anonymous Coward | more than 3 years ago | (#36258806)

is like saying a map of downtown Boise is a map of the USA

Redshifts, red = moving away and blue = closer? (1)

Aldenissin (976329) | more than 3 years ago | (#36258808)

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 believe to actually be said positions from redshifting. Even more awesome would be a time slider where the colors changed to red/blue if the relative vector changed.

But then, while they say 3d, I only see a 2d image, so I don't know if they've actually mapped out positions in 3d space or just merely color coded the redshift. If that took ten years, I guess we'll have to wait for quantum computers to do all of the heavy lifting automagically.

Re:Redshifts, red = moving away and blue = closer? (0)

Anonymous Coward | more than 3 years ago | (#36259124)

By the looks of the key every object in this diagram is red shifted.
They seem to have used red to show the most red-shifted objects, and blue to show the least red-shifted objects.

Re:Redshifts, red = moving away and blue = closer? (1)

camperdave (969942) | more than 3 years ago | (#36259850)

Yes, Gilligan, because the universe is expanding, everything is moving away. Thus everything is red-shifted.

Re:Redshifts, red = moving away and blue = closer? (0)

Anonymous Coward | more than 3 years ago | (#36259280)

you've misinterpreted the redshift scale in the diagram (or rather you've misinterpreted the colour scheme).
all of the redshifts labeled are z > 0.
seriously, google is your friend. also reading is your friend.

Re:Redshifts, red = moving away and blue = closer? (1)

digitalchinky (650880) | more than 3 years ago | (#36259346)

What color is the stuff that's not red shifted? :-)

Re:Redshifts, red = moving away and blue = closer? (1)

Aldenissin (976329) | more than 3 years ago | (#36259528)

Well apparently he can't read yet wants others to. (Typical coward...) Just because it's called redshifted, it often is used to describe a shifts period, unless you need to be specific and then you might say blue. Don't blame me, it's like crackers being called hackers. Related yes, same thing no, but that is how it is used.

While of course rarer, I am pretty sure there are objects moving toward the Milky Way. IF that isn't represented, it should be noted. Perhaps it was in that key, but sparse keys will lead to confusion. I am sure I am not the only one who made an error if I did because they don't understand esoteric symbols, but can still comprehend the significance.

Re:Redshifts, red = moving away and blue = closer? (1)

boristhespider (1678416) | more than 3 years ago | (#36260652)

Of course there are objects moving towards us, quite a lot of them when you look towards the Virgo supercluster (because we're falling into it). However they tend to be extremely nearby, as far as cosmological distance scales go. The universal expansion is known as the "Hubble flow", and it grows rapidly as you look further and further away from us, and quickly swamps any local motion (known as "peculiar motion", although the terminology is imprecise and sometimes that only refers to the motion as projected onto the celestial sphere, perpendicular to the line of sight).

These very low redshift (and blueshift) objects will be removed -- my guess is that they'll have done a cut and removed everything below z=0.05 or z=0.1 or so. That will remove all the local structure which would otherwise contaminate the cosmological plot. (Yes, you could argue it would also remove any odd outliers that are far away *and* flying towards us, but such weird objects would be flagged and basically there aren't any.)

But I'm not involved in 2MASS and it's literally four or five years since I went to a seminar given by anyone involved, so maybe they're doing something very different - this is all just my guess.

Re:Redshifts, red = moving away and blue = closer? (1)

Black Parrot (19622) | more than 3 years ago | (#36259716)

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

Re:Redshifts, red = moving away and blue = closer? (1)

boristhespider (1678416) | more than 3 years ago | (#36260730)

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.

Re:Redshifts, red = moving away and blue = closer? (1)

dotancohen (1015143) | more than 3 years ago | (#36260616)

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!

Re:Redshifts, red = moving away and blue = closer? (1)

Chardansearavitriol (1946886) | more than 3 years ago | (#36260720)

Indeed. One thing that many laymen make a mistake of is assuming that Earth is a closed system. Entropy must increase, but may not be meaningful; we'll be living it up without issue until the sun grows and obliterates the planet. So yep! One of the bizarre things about the galactic filaments, is the density fluctuates into areas of high and low mesh, creating that pretty web. In the end, all things wil llikely expand away from all thigns (thus causing heat death.) But I guarantee you, and everyone, that when the universe dies from heat death, it wont be our problem. It is unknown how entropy effects heaven but i dont know any atomic angels so, that should be a fun ride to watch.

Re:Redshifts, red = moving away and blue = closer? (1)

Chardansearavitriol (1946886) | more than 3 years ago | (#36260706)

You are correct in the red and blue parts. This might be helpful; Its the Doppler effect but with light instead of sound.

You are here. (0)

Anonymous Coward | more than 3 years ago | (#36258894)

You are here.

There be Bogs (1)

oldhack (1037484) | more than 3 years ago | (#36259046)

There be Borgs.

Sweet! (1)

Greyfox (87712) | more than 3 years ago | (#36258910)

Now all it needs is a microscopic dot on a microscopic dot labeled "You are here"

Schrodinger's Dot (1)

Tablizer (95088) | more than 3 years ago | (#36259950)

or, maybe not

Re:Sweet! (0)

Anonymous Coward | more than 3 years ago | (#36260534)

It's already there. You just need better glasses to see it.

MMO (0)

Anonymous Coward | more than 3 years ago | (#36259076)

I hope this gets mapped into STO

Boring... (1)

OpenLegs (2203438) | more than 3 years ago | (#36259082)

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.

Celestia? (2)

thelandp (632129) | more than 3 years ago | (#36259284)

We need to see this in Celestia!

Does the internet accept the challenge?

Re:Celestia? (1)

Trogre (513942) | more than 3 years ago | (#36259308)

Damn, you beat me to that comment!

Re:Celestia? (1)

Dasher42 (514179) | more than 3 years ago | (#36260552)

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.

Re:Celestia? (1)

phme (1501991) | more than 3 years ago | (#36260930)

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.

Weird spiderweb/neuron concentrations (1)

GodfatherofSoul (174979) | more than 3 years ago | (#36259452)

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.

Re:Weird spiderweb/neuron concentrations (1)

Aldenissin (976329) | more than 3 years ago | (#36259562)

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.

Re:Weird spiderweb/neuron concentrations (2)

buchner.johannes (1139593) | more than 3 years ago | (#36259744)

Here are good starting points on voids [wikipedia.org] and filaments [wikipedia.org] .

Re:Weird spiderweb/neuron concentrations (2)

boristhespider (1678416) | more than 3 years ago | (#36260664)

....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 given that the standard cosmological model works so damned well, but there are enough odd features (dark energy, for example) that suggest something slightly odd might be going on with this implicit averaging. Or of course the averaging could work fine and it's actually a scalar field slowly rolling down its potential, or a manifestation of two branes moving slowly closer to one-another, or a reduction in gravity's effects at low curvatures or.....)

Re:Weird spiderweb/neuron concentrations (1)

Chardansearavitriol (1946886) | more than 3 years ago | (#36260792)

Nature likes to watch us squirm. "Cute infinity symbol." as a response to all mathematical endeavors.. "You cant ever reach the lowest possible temperature no matter how hard you try." on absolute zero. Of course, thats putting things in a human perspective. It'll probably a lot more like "You cannot grasp the true form of Giygas' attack!"

Re:Weird spiderweb/neuron concentrations (1)

boristhespider (1678416) | more than 3 years ago | (#36260878)

Err, thanks.

Re:Weird spiderweb/neuron concentrations (1)

Hadlock (143607) | more than 3 years ago | (#36261062)

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.

Obligatory Steven Wright paraphrase (1)

niktemadur (793971) | more than 3 years ago | (#36259490)

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.

Re:Obligatory Steven Wright paraphrase (0)

Aldenissin (976329) | more than 3 years ago | (#36259588)

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)?

Re:Obligatory Steven Wright paraphrase (0)

Anonymous Coward | more than 3 years ago | (#36259768)

Mega-Whoosh. Please log out immediately. You may log back in once you have read and understood the links below. Optionally, you may also attempt to procure a sense of humour.

Star Wars Episode IV: A New Hope [wikipedia.org]
Millennium Falcon [wikipedia.org]

Blank spot (1)

yrrah (1247500) | more than 3 years ago | (#36259614)

Why is there a big empty space near the "equator" of the picture?

Re:Blank spot (1)

mhotchin (791085) | more than 3 years ago | (#36259712)

Obscured by the dust in our own galaxy.

Re:Blank spot (1)

treeves (963993) | more than 3 years ago | (#36260240)

As mentioned by the summary. Etc.

Re:Blank spot (0)

Anonymous Coward | more than 3 years ago | (#36260692)

OMFG FTFA!

Earth's faith is doomed... (1)

GPLHost-Thomas (1330431) | more than 3 years ago | (#36259790)

If the Vs get to know that map, they will locate us, and we're done!

Wow. Bagger. (0)

Anonymous Coward | more than 3 years ago | (#36259890)

I like to think that, from the right perspective, the path between all of these galaxies spells out a very, very rude word.

Observations indicate that the map must be wrong (1)

Eukariote (881204) | more than 3 years ago | (#36259920)

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 torrent can be found here [isohunt.com] for example.

Re:Observations indicate that the map must be wron (1)

boristhespider (1678416) | more than 3 years ago | (#36260678)

..... 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.

Re:Observations indicate that the map must be wron (1)

Eukariote (881204) | more than 3 years ago | (#36260758)

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 yielding, by any commonsense definition, a wrong map.

Secondly, the redshift is proportional to distance dogma is so ingrained in astronomical teaching and literature that authors assume distance to be implied by a mere mention of a redshift measurement: the reader is supposed to know how to factor out the Hubble constant if units of distance are desired. As such, the use of redshift as a map coordinate can be assumed to have the intent to imply a spatial dimension unless explicitly mentioned otherwise.

Re:Observations indicate that the map must be wron (1)

boristhespider (1678416) | more than 3 years ago | (#36260866)

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 about* is in redshift space. What's your argument with that? They've looked at the distribution on the celestial sphere and plotted up everything with redshifts above some cut-off, whether that cut-off is z=0 or z=0.01 or wherever they put it. It's just a plot of redshifts. No assumptions made about anything.

As for this "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", that's simply wrong. I can use it as a dimension if I want. I could convert it to velocities and use that quite happily -- although as you rightly point out that assumes that the entire redshift is given by a velocity. In a standard cosmology at least the vast bulk of the redshift is given by a velocity. You're free to reinterpret the data through your own model, of course. I could even sit there and examine each and every galaxy there and find the colour of it and plot that as a dimension instead. I could convert that colour to an approximate temperature and use that as a third dimension. It's you that's then interpreting that as a distance right now -- and I suspect you're doing that so you can then attack the standard model.

Good on you, the standard model is riddled with holes and I work on attacking some of those holes myself. But don't set up an immediate strawman. That plot is in redshift, and that's a perfectly valid variable to use. Furthermore, it's hte *only* variable they can use that doesn't involve any extra assumptions. As soon as you swap it to *anything else*, whether it's from your own little pet model or from standard Lambda CDM or anything else, it's model-dependent. The redshifts are what are observed, ergo that's what they've put on this plot.

I seriously don't see an issue with that.

For everything else it's pretty irrelevant to the plot, and in the press release obviously they're going to simplify down for a general audience. And as I said, you can feel free to take the raw data, or take the filtered data (where the redshifts have been calculated, doubtless using photometric redshifts which certainly contaminate the data but at a controllable rate given the sheer size of 2MASS which will beat down the statistical error), and do your own analysis. Indeed, please do. Lambda CDM is a startlingly succesful model and has beaten off anything else simply because it *FITS*, but I don't think anyone is seriously sold on it, other than it works. All of us would love something more interesting. Fewer people would love the ditching of a FLRW background entirely, chiefly because they don't have the background necessary to work with something more complicated, but there are those of us that want to drop that assumption too. But you have to be able to fit the data at least as well as Lambda CDM does otherwise you're going to be ignored just as pretty much every other alternative is ignored.

Where are we (milky way) on the map? (0)

Anonymous Coward | more than 3 years ago | (#36259994)

Anyone know? Are we in the centre?

Re:Where are we (milky way) on the map? (1)

boristhespider (1678416) | more than 3 years ago | (#36260684)

that's the view as seen from earth. so we can't be represented on that map at all -- that's what we see surrounding us, except that the celestial sphere has been mapped onto a 2d plane. you can transform that map back and put it on a sphere, and then yes, we'd be in the centre of the sphere.

Why is the equator empty? (1)

MartinSchou (1360093) | more than 3 years ago | (#36260096)

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:Why is the equator empty? (3, Informative)

pherth (777159) | more than 3 years ago | (#36260130)

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.

Re:Why is the equator empty? (2)

HuguesT (84078) | more than 3 years ago | (#36260212)

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.

You are here (1)

Saphati (698453) | more than 3 years ago | (#36260488)

Where is the 'You are here' marker?

Need the plans for my 3d printer (0)

Anonymous Coward | more than 3 years ago | (#36260624)

Torrent plz

"out to a distance of 380 million light-years" (2)

ciaran_o_riordan (662132) | more than 3 years ago | (#36260716)

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.

How handy... (1)

lexsird (1208192) | more than 3 years ago | (#36260722)

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 GPS?

I enjoy reading these type of subjects (0)

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