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Astronomers Find Most Distant Protocluster of Galaxies

Soulskill posted about 2 years ago | from the since-before-your-sun-burned-hot-in-space dept.

Space 129

The Bad Astronomer writes "Using the monster 8.2-meter Subaru telescope, astronomers have identified the most distant cluster of galaxies ever found: a collection of galaxies at a staggering distance of 12.7 billion light years. This is the most distant cluster ever seen that has been confirmed spectroscopically (PDF). Technically, it's a protocluster, since it's so young — seen only a billion years after the Big Bang itself — the cluster must still be in the process of formation."

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129 comments

upgraded to include... (2, Funny)

CosaNostra Pizza Inc (1299163) | about 2 years ago | (#39917993)

Includes all-wheel drive and a boxer-engine.

Re:upgraded to include... (0)

Anonymous Coward | about 2 years ago | (#39918049)

Waiting for the twin turbo spec b myself.

Re:upgraded to include... (4, Insightful)

busyqth (2566075) | about 2 years ago | (#39918387)

Actually look at the Subaru Car logo and consider the meaning of "Subaru" and you'll see why the discovery of a galaxy cluster is very fitting for the Subaru telescope...

Re:upgraded to include... (1)

tinkerton (199273) | about 2 years ago | (#39919299)

Damn. Randall Munroe drives a Scooby?

Re:upgraded to include... (0)

Anonymous Coward | about 2 years ago | (#39919763)

Scoobaru? huh?

Re:upgraded to include... (2)

tinkerton (199273) | about 2 years ago | (#39920841)

Kidding. Just that his favorite astronomical entity is the Pleiades. And the Scooby is, well, associated to a different kind of person.

incredible (4, Insightful)

Anonymous Coward | about 2 years ago | (#39918031)

It is incredible what we can accomplish as humans, imagine if we did not waste trillions on useless battles for the hear and minds of primitive retarded people with stone age believes.

Re:incredible (5, Funny)

Anonymous Coward | about 2 years ago | (#39918213)

Yes, we could spend some of that to educate folks like yourself on how to write properly!

Re:incredible (0)

Anonymous Coward | about 2 years ago | (#39918715)

What an idiotic statement.

Re:incredible (0)

Anonymous Coward | about 2 years ago | (#39922527)

Congratulations, you've managed to turn a noble sentiment of hope, progress, and free thought into fucking racism. Imagine what you as a writer could accomplish if you didn't spend effort on internet put-downs and Bush-era xenophobia.

Soo.... (1)

Anonymous Coward | about 2 years ago | (#39918045)

So.... It's almost as old as your mom?

Well, that's where it was... (1)

White Flame (1074973) | about 2 years ago | (#39918051)

12.7 billion years ago it might have been 12.7 billion light years away, but where is it now?

Re:Well, that's where it was... (4, Interesting)

arth1 (260657) | about 2 years ago | (#39918227)

12.7 billion years ago it might have been 12.7 billion light years away, but where is it now?

Exactly where we see it. The 12.7 billion years haven't passed, because there is no common point of reference between us and them for that time to have passed in.
"Now" and "then" makes no sense except for local distances, without introducing FTL, time travel and violating causality. We can only measure round trip times, not one way time.
The photons haven't experienced 12.7 billion years of travel - they just left.
If this makes your head hurt, good.

Re:Well, that's where it was... (1)

gstoddart (321705) | about 2 years ago | (#39918311)

The photons haven't experienced 12.7 billion years of travel - they just left.
If this makes your head hurt, good.

Wait, what? If the photons travelled at the speed of light, they've been doing that for 12.7 billion years.

Assuming photons can count and measure time, would they really "see" this as instantaneous? Or would they have had time to catch up on their reading?

Relativity and light speed are so damned confusing some times.

Re:Well, that's where it was... (5, Informative)

MightyMartian (840721) | about 2 years ago | (#39918405)

Short answer: yes. For anything traveling at luminal speeds, time is not perceived. If you were a photon, it might take you 12.7 billion years to get here, but for you it is an instant.

Re:Well, that's where it was... (1)

Anonymous Coward | about 2 years ago | (#39918437)

I think he's wrong.

From the photon's point of reference, it traveled instantaneously. From our point of reference, it took 12.7 billion years for the photons to reach us.

Therefore, what we're seeing is how it looked 12.7 billion years ago.

Re:Well, that's where it was... (2)

arth1 (260657) | about 2 years ago | (#39918699)

From the photon's point of reference, it traveled instantaneously. From our point of reference, it took 12.7 billion years for the photons to reach us.

Therefore, what we're seeing is how it looked 12.7 billion years ago.

Your error is to apply the word "ago". That implies that time passes here and there in the same frame of reference - a universal clock, if you like. That doesn't exist - time is only a local phenomenon.

From our point of view, it did not take 12.7 billion years for the photons to get here, because from our point of view, 12.7 billion years ago, that part of the universe didn't exist. There is no "then" common to us and them; only a blossom slowly opening and revealing parts of the universe to us that's new to us.

Re:Well, that's where it was... (3, Insightful)

gstoddart (321705) | about 2 years ago | (#39918961)

because from our point of view, 12.7 billion years ago, that part of the universe didn't exist

Oh come on, do you guys just make this stuff up as you go? ;-)

No, seriously, I actually understood that we were seeing what was there 12.7 billion years ago -- WTF does it mean then? I thought this was what existed 12.7 billion years ago from our point of view.

only a blossom slowly opening and revealing parts of the universe to us that's new to us

That sounds dirty, and I'm not sure if it actually sheds any, er, light on this.

I think this actually confirms what I knew in university -- astrophysicists must spend much of their time drunk in order to be able to reconcile this stuff with everything else.

Re:Well, that's where it was... (2)

arth1 (260657) | about 2 years ago | (#39919157)

No, seriously, I actually understood that we were seeing what was there 12.7 billion years ago

There you use that word again. "Ago" doesn't make sense at relativistic speeds and vast distances.

It's 12.7 billion light-years distant. Light-year is a distance, not an age.
If you travelled that distance and back at the speed of light, we would have to wait 25.4 billion years for your return. But your travel would not take that time. A person at your turning point, 12.7 billion light years distant, would not have seen you 12.7 billion years ago when you come back to us. He would just have seen you leave, and you would agree. For you, the universe contracted into near nothing and aged rapidly - for him, that aging hasn't happened yet.

Re:Well, that's where it was... (1)

Clith (5063) | about 2 years ago | (#39919165)

12.7 billion years ago our point of view didn't exist either. The universe was only around 1 billion light-years across. You might think that would mean all light would arrive at a destination in 1 billion years or less. You would be wrong. :-)

Re:Well, that's where it was... (4, Interesting)

Lithdren (605362) | about 2 years ago | (#39919183)

All it really proves is that humans cannot comprehend distance as vast as this.

My understanding, and im sure its flawed, is that something like a Photon doesn't experience time. To it, it pops into and out of existance, one end at the surface of a star in a galaxy cluster 12.7 billion light years away, the other end at the Subaru telescope in this case. Just as suddenly as this happends, its gone again.

This is because its traveling at the speed of light. Time and space are linked. Beyond this my understanding breaks down, but I suspect it has something to do with moving through space at that speed, and our misunderstanding of what time really is. We experience time where there is a 'universal' time in our refrence, because really anything we need to reference is already here, moving with us at the same speed around the sun. There is no 12.7 billion years ago to this galaxy, per our reference, because nothing that is happening 'now' as you and I understand it can possibly affect us here, without violating the speed of light. We're not looking at a galaxy we're literally looking back in time at a galaxy. If this galaxy exploded ripping a hole in the fabric of space-time and ended the entire universe right now, we'd not be aware of it for another 12.7 billion years. Per our reference, nothing has happened, or will happen, for that span of time. So in effect, for us, what we're seeing is what IS happening.

Now please correct my misunderstanding, those of you lurking out there who do know better, because i'd love to understand all this!

Re:Well, that's where it was... (1)

arth1 (260657) | about 2 years ago | (#39918503)

Wait, what? If the photons travelled at the speed of light, they've been doing that for 12.7 billion years.

Only from an outside point of view, of which there are none. We only see the end of their travel.
From their point of view (if you could piggy-back on them in a space ship going the same speed), only an instant has passed, while the rest of the tiny universe aged.

Relativity and light speed are so damned confusing some times.

It sure is. One of the most difficult thing to grasp is that time is a purely local phenomenon, and that you can't apply "now" to anywhere else. Even such a thing as "the age of the universe" is our age of the universe. What the age of the universe is elsewhere is meaningless, because there is no universal "now" clock ticking away seconds.

Re:Well, that's where it was... (1)

gstoddart (321705) | about 2 years ago | (#39918805)

It sure is. One of the most difficult thing to grasp is that time is a purely local phenomenon, and that you can't apply "now" to anywhere else.

May I be excused? My brain is full [flickr.com].

I honestly don't know how physicists keep it straight -- verb tenses must be a bitch. When the photon will have arrived yesterday after it's long journey of instantaneous, we will have known tomorrow what something looked like billions of years ago but never not almost today. Next year, we might know what happened before that.

Somehow I have a vision of a bunch of physicists all trying to convince themselves and one another that they follow this. Possibly precede or happen at the same time, I'm confused.

Re:Well, that's where it was... (1)

Anonymous Coward | about 2 years ago | (#39919135)

Actual physicists would probably tell you that if we could get a decent handle on the cluster's state and location 12.7 billion years ago from these visual observations, we could make a reasonable projection, taking the two reference frames into account, as to the cluster's current state and location. It is still out there, somewhere, right now, in some state.

All the pseudo-mysticism in this discussion is a load of nonsense by geeks trying to sound intelligent.

Re:Well, that's where it was... (1)

NemoinSpace (1118137) | about 2 years ago | (#39922767)

All the pseudo-mysticism in this discussion is a load of nonsense by geeks trying to sound intelligent.

ftfy

Re:Well, that's where it was... (1)

tibit (1762298) | about 2 years ago | (#39919321)

Terry Pratchett took this to the logical conclusion in his vision of the Discworld. Listen in to some conversations going on at the Unseen University, and generally with wizards in Discworld, and you'll hear stuff that makes just about as much "sense". Nature is a bitch :)

Re:Well, that's where it was... (1)

l0ungeb0y (442022) | about 2 years ago | (#39918377)

The photons haven't experienced 12.7 billion years of travel - they just left

Implying the photons were teleported straight to the lens of the Subaru Telescope. Unless you can show that those photons somehow violated or evaded the constant "c", you can damn well bet your ass those photons have experienced a duration of travel at the speed of light from their point of radiation to our planet's present position.

Re:Well, that's where it was... (2)

_0xd0ad (1974778) | about 2 years ago | (#39918419)

The speed of light is infinite, because due to relativistic effects, time has stopped. Only an outside observer sees something moving at the "speed of light"; to the photon itself, no time passes.

Re:Well, that's where it was... (1)

Anonymous Coward | about 2 years ago | (#39918825)

OK, I get that. But we aren't talking about photons here really. We are talking about something on the other end - where the photons come from. That isn't a photon and it isn't moving at the speed of light. While true that we can only get information about that place via photons, it is not true that we are observing that far off location as it is today. Sure the photons have experienced relativity, but the location hasn't. For example:

Let's say I am 1,000 light years away and I flip you off.
By the time you see it, I am dead and gone.
I don't care that the photons "just left" - that's all because of relativity. The two locations that are 1,000 light years apart are still incapable of observing each other in realtime- there is a "broadcast delay" of 1,000 years. So when you see that I flipped you off, you can just say "but - neener neener - you are dead, dumbass (and so I would be). All this talk about there not being any framework for observation and all is just hocus pocus. Duration has in fact been in effect.

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39919439)

In your example, we only know that it took 1000 years to reach Earth. At your remote location, time "passes" slower or faster than it does on Earth. It depends on your velocity as you fly through the universe and some other things I won't mention. We cannot measure that velocity, because there is no universally stationary object to derive a relative speed from. Therefore, we have no way to know how fast or slow time "passes" when compared to how time "passes" on Earth.

Because we do not know, we cannot make an assumption about the remote location. Therefore, we don't consider it. It's irrelevant to the discussion.

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39919617)

Actually that's still not true. The speed of light isn't just any other speed, it is intimately connected to space. At the speed of light, the time axis and space axis align. It isn't a broadcast delay, it is actually 100% really a reality delay. 'c' is the speed of time as well as light. Things that happen 1000ly away from us are happening now. There is no meaning to "simultaneous" at that distance.

Re:Well, that's where it was... (2)

ScentCone (795499) | about 2 years ago | (#39919603)

Only an outside observer sees something moving at the "speed of light"; to the photon itself, no time passes.

Not really. This was a research project, which means the very last part of the photon's trip was through part of academia. Which means it felt like exactly like 12.7 billion years.

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39918573)

"c" is relative to Earth.

From the photon's point of reference, it travelled instantaneous.

Re:Well, that's where it was... (2)

arth1 (260657) | about 2 years ago | (#39918747)

Implying the photons were teleported straight to the lens of the Subaru Telescope.

No, implying that distance and time aren't constants, but vary depending on your frame of reference.

Re:Well, that's where it was... (1)

l0ungeb0y (442022) | about 2 years ago | (#39919301)

So you are denying that the astronomers who captured these photons with their telescope have a frame of reference?
Saying the duration of travel a photon experiences is imaterial because the photon has no awareness is saying that there is no sound if a tree falls in the woods and no one is there to hear it. We all know that it *must* have interacted with the atmosphere and made a sound -- regardless of anyone being there to hear it. As such, the light traveled at the speed it always travels, we happen to observe it at 12.7 Billion years by our frame of reference.

Trying to "blow peoples" minds with relativity doesn't really work when it relies on the person discounting their own existence. We observed it, therefore our frame of reference is the only one that matters.

Re:Well, that's where it was... (2)

arth1 (260657) | about 2 years ago | (#39923211)

So you are denying that the astronomers who captured these photons with their telescope have a frame of reference?

No common frame of reference? Yes, most certainly there isn't one, and the astronomers would agree. They only capture the photons as they arrive here, and can tell by the red-shift how far away the proto-galaxy is. But they can't tell anything about time, because the speed of time itself can't exceed the speed of light - there's no big Pratchettian clock that ticks time for everywhere in the universe.

When something happens elsewhere, it hasn't happened at all until the light cone hits us. Or, to put it another way, it's impossible to synchronize two clocks that are at any distance. You can set both to a time that appears to be the same for an observer in a third spot, but if you do so, they're not synchronized - an observer at A will think that its own clock is both preceding and running faster than the other clock, and an observer at B will think the exact same about its own clock.
Time is a local phenomenon, and this is very difficult for us to grasp because we're always experiencing the local time. To us, it ticks away at a constant rate, but this is an illusion.

Re:Well, that's where it was... (1)

Dinghy (2233934) | about 2 years ago | (#39919791)

12.7 billion years ago it might have been 12.7 billion light years away, but where is it now?

Exactly where we see it. The 12.7 billion years haven't passed, because there is no common point of reference between us and them for that time to have passed in. ... If this makes your head hurt, good.

It doesn't make my head hurt, I just have a simple question that causes me to believe differently.

If you left our current location 12.7 billion years ago, and were travelling at the speed of light in the exact direction that these photos came from, and then stopped so you could be easily observed, would you currently be where the protocluster is, or will it have moved?

Re:Well, that's where it was... (1)

arth1 (260657) | about 2 years ago | (#39923295)

If you left our current location 12.7 billion years ago, and were travelling at the speed of light in the exact direction that these photos came from, and then stopped so you could be easily observed, would you currently be where the protocluster is, or will it have moved?

"12.7 billion years ago" would be in our time frame.
But your "currently" would not be.
It is meaningless to say you travel for 12.7 billion years at the speed of light, because to the world you departed, you have left reality, and to yourself, no time has passed at all.

Instead, you can imagine that you travel a distance of 12.7 billion light years. Which isn't the same. And no, it won't bring you back to that proto-galaxy. In the zero seconds your travel took, the universe has expanded. You'll arrive at this new location seriously red-shifted. Continuing your journey towards the proto-galaxy based on new observations would be a relativistic version of Xeno's paradox, where you, the hare, can never overtake the turtle.
And it's turtles all the way down.

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39920331)

12.7 billion years ago it might have been 12.7 billion light years away, but where is it now?

Exactly where we see it. The 12.7 billion years haven't passed, because there is no common point of reference between us and them for that time to have passed in.
"Now" and "then" makes no sense except for local distances, without introducing FTL, time travel and violating causality. We can only measure round trip times, not one way time.
The photons haven't experienced 12.7 billion years of travel - they just left.
If this makes your head hurt, good.

How the fuck did this get "Informative"? It's total bullshit. Informative is the worst tag on slashdot, it implies the moderators somehow, by being moderators, know what's true more than other users, (or, at all...) which in this case they clearly don't.

Time passes for all things. Photons just as anything else. Just because they're going really fast doesn't mean somehow time isn't passing for them, so you're mistaken. They've experienced the same amount of time, for all intents and purposes.

If this makes your ego hurt, good.

Eppur si muove (1)

arth1 (260657) | about 2 years ago | (#39923603)

How the fuck did this get "Informative"? It's total bullshit. Informative is the worst tag on slashdot, it implies the moderators somehow, by being moderators, know what's true more than other users, (or, at all...) which in this case they clearly don't.

Time passes for all things. Photons just as anything else. Just because they're going really fast doesn't mean somehow time isn't passing for them, so you're mistaken. They've experienced the same amount of time, for all intents and purposes.

You just don't understand relativity, AC. What you're saying is very much like claiming that ships would fall off the edge of the earth if it were round, or that the earth can't circle the sun because we would fall off and burn to a crisp. You cling to Newtonian time, just as your forefathers clung to the Ptolemaic world view.

That time passes differently depending on your speed is now indisputable - even satellite clocks used for GPS have to compensate for that! The faster you go, the more profound the effect. As you approach the speed of light in vacuum, the passage of time approaches zero. At c, it is zero.
This precludes any universal time as Newton (and you) perceived it. It is always a local phenomenon.
See http://en.wikipedia.org/wiki/Relativity_of_simultaneity [wikipedia.org] for more details.

Re:Well, that's where it was... (2)

Bergs007 (1797486) | about 2 years ago | (#39918251)

The funny thing about relativity is that is that in our frame of reference, this is happening NOW, not 12.7 billion years ago.

Re:Well, that's where it was... (2)

Loughla (2531696) | about 2 years ago | (#39918307)

That's what I've never understood. For it to be happening right now, to me, it stands to reason that if we look far enough away we could see the light from the big bang. Which means that everything that has ever happened is always happening everywhere. Which means that we always have existed in the state that we exist in today and will always exist in the state that we existed in billions of years ago.

Oh no, I've gone cross-eyed.

Re:Well, that's where it was... (3, Interesting)

MightyMartian (840721) | about 2 years ago | (#39918451)

You couldn't see light from the Big Bang itself because it took until nearly 400,000 years after the Big Bang for the Universe to cool sufficiently for photons to find a clear path through the charged ions. It's this first wave of freed photons that form the Cosmic Microwave Background Radiation.

Re:Well, that's where it was... (1)

Loughla (2531696) | about 2 years ago | (#39918461)

That didn't help my brain.

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39918521)

Mind = blown [joeydevilla.com]. Fun stuff, eh?

Re:Well, that's where it was... (1)

MightyMartian (840721) | about 2 years ago | (#39918985)

I'm not sure what's confusing you. Look, how time is perceived (excluding any particular psychological phenomena) is a function of speed of the object in question; it's all relative to the frame of reference of the observer. The faster you go, the slower external time passes (not your own time, mind you, just the time of anything not moving as fast as you are). The closer to the speed of light you go, the slower time passes, until finally you have a photon which always moves at the speed of light, time does not pass at all from that frame of reference. That's not to say that nothing happens during the lifetime of a photon, it's just from the photon's frame of reference.

It is a counter-intuitive notion, to be sure, but one that has been confirmed many times. It does not mean that there is no time at all. All measurements, of course, are from the frame of reference of folks in the Local Group, more or less. Some observer in some other part of the universe moving at some different speed would measure the time differently.

Re:Well, that's where it was... (1)

uhuru_meditation (2573595) | about 2 years ago | (#39919217)

Did time existed before universe was created? Are first ever protons created the holy grail of time/space? Where is the initial first light from the Big Bang? - according to this theory it didn't arrive yet or suntin. I have wasps in my brain... (faints)

Re:Well, that's where it was... (1)

MightyMartian (840721) | about 2 years ago | (#39919247)

Other than some string theorists, I think most physicists are of the opinion that time-space did not exist prior to the Big Bang.

Re:Well, that's where it was... (1)

Kozar_The_Malignant (738483) | about 2 years ago | (#39920977)

Other than some string theorists, I think most physicists are of the opinion that time-space did not exist prior to the Big Bang.

According to string theorists, prior to the Big Bang, the Silly String was in the Big Can. Then it was squirted out forming the universe. One variant of this holds that it was Pasta not Silly String.

Re:Well, that's where it was... (1)

Dishevel (1105119) | about 2 years ago | (#39918883)

it stands to reason that if we look far enough away we could see the light from the big bang

This [wikipedia.org] is pretty much what you are looking for.

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39920285)

You can't see the light directly from the big bang, since at that time the universe was too hot for photons to form from the quarks, and too many ions in the way for them to travel at all.
This happened 'slightly' later, roughly half a million years after the big bang.

As for the light from half a million years after the big bang, well yes that you CAN see.
Those waves of light have been traveling through space since the moment photons could move, and during that time space has expanded greatly. The expansion itself has stretched the light waves out.
At first they were visible light (actually all frequencies) however after being stretched the visible light is now in the microwave range.
Turn on your TV to an unused channel, and it will pick up microwave frequencies in a small section of that spectrum. See the static? Some of that is the very photons emitted from that half-million year after the big bang period. The rest is local microwave sources. They all look the same at this point however.

Re:Well, that's where it was... (1)

Java Pimp (98454) | about 2 years ago | (#39918271)

Probably long dead. Since these were the "first" stars/galaxies from the beginning of the universe, they've long since exploded and are now part of the "near by" most recent stars and galaxies we're most familiar with. They are part of us.

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39918299)

That is the complicated part of astronomy. Nothing is really where it appears to be. And the stuff you see farther away has actually moved even more. And then there is stuff whose light won't reach us...

Time & space... interesting to think about, but it makes my brain go to 100%. :)

Re:Well, that's where it was... (4, Informative)

NEDHead (1651195) | about 2 years ago | (#39918321)

Wrong on several counts. What the 12.7 refers to is when the light left the cluster in question (in billions of years). At the time the light left the cluster it was actually much closer to us than 12.7 light years. The observable universe is actually larger in light years than the time since the Big Bang, due to the expansion of space. This expansion also stretched the travel time for the cluster's light to reach us. Now the cluster (to the extent 'Now' has any meaning) may be 25+ light years away (I apologize for the imprecision, as I don't have the exact figures at hand).

Re:Well, that's where it was... (0)

Anonymous Coward | about 2 years ago | (#39918517)

how can you mods possibly score this reply a 2!
The guy is telling you correctly how it works.

idiot slashdot moderators.

Re:Well, that's where it was... (1)

arth1 (260657) | about 2 years ago | (#39919275)

how can you mods possibly score this reply a 2!

He's 9 orders of magnitude off, for starters.

And they didn't mod him a 2 - that was his karma bonus.

Re:Well, that's where it was... (1)

NEDHead (1651195) | about 2 years ago | (#39919473)

Ah, my bad on the billions. I noted it near the beginning but dropped it as I continued. Please accept my apology for the mis-translation, as my planet has a very, very large orbit.

Re:Well, that's where it was... (2)

bhagwad (1426855) | about 2 years ago | (#39918329)

There is no absolute "now" in the universe since we have the concept of relative simultaneity. The photons reaching us from there have "just left" according to them even though they may seem to have traveled a huge distance according to a third party observer. Since time dilates and space shrinks as you approach the speed of light, every photon reaches its destination "instantly"

So while we can talk about "now" and "then", it's meaningless on an absolute scale. For this reason, when light from someplace reaches us, we treat it as if it's happening "now". Because if you were a photon, you would reach every place instantly.

Re:Well, that's where it was... (2)

anonymousNR (1254032) | about 2 years ago | (#39918681)

Dont know accurately, though there is a way to measure that. but based on Dark energy theory,It would be around 40 billion light years away right now.

That's a big Subaru. (0)

Anonymous Coward | about 2 years ago | (#39918173)

It's all that one needs to travel the galactic outback.

Re:That's a big Subaru. (0)

Anonymous Coward | about 2 years ago | (#39918289)

Well, that and a towel.

Not quite a young cluster (1)

Tha_Big_Guy23 (603419) | about 2 years ago | (#39918205)

the cluster must still be in the process of formation.

Well, it's still in the process of formation where we can visibly see it. Given that it's 12.7 billion light years away, I'd like to believe that the galaxies are properly formed at this point. Though, given that not one person knows exactly how long it takes to form a proper galaxy, who's to say that it isn't finished. It's all best guess I suppose. Really cool science though, knowing that light from 12.7 billion years ago is illuminating our planet, however faint it may be.

Re:Not quite a young cluster (3, Interesting)

Java Pimp (98454) | about 2 years ago | (#39918317)

Perhaps the universe is in fact curved and 12.7 billion years "across" and we are looking at the formation of the milky way and other local galaxies...

Re:Not quite a young cluster (0)

Anonymous Coward | about 2 years ago | (#39918483)

Perhaps the universe is in fact curved and 12.7 billion years "across" and we are looking at the formation of the milky way and other local galaxies...

Quick call CSI, they can zoom and enhance on the image and use it to solve the galaxies first cold case!

Re:Not quite a young cluster (1)

Surt (22457) | about 2 years ago | (#39918835)

No, we have enough evidence to know that isn't true. There are plenty of galaxies visible with the wrong masses to tell us that if the universe is curved the curvature doesn't loop within the size of the visible universe.

Re:Not quite a young cluster (1)

bhagwad (1426855) | about 2 years ago | (#39918361)

There is no "at this point" since absolute simultaneity doesn't exist in the universe. Consider this: The photons reaching us from that place have only "just left" according to them! So for us to say "right now" means very different things depending on your frame of reference.

Re:Not quite a young cluster (0)

Anonymous Coward | about 2 years ago | (#39918471)

Why are you talking about what the photons "experience" when the conversation is about the location where the photons originated?

"still in the process of formation" (1)

Anonymous Coward | about 2 years ago | (#39918207)

Technically, it's a protocluster, since it's so young — seen only a billion years after the Big Bang itself — the cluster must still be in the process of formation.

Scientists may only be detecting its protocluster stage because the light from its current stage hasn't made it here yet, but I'm willing to bet good money that it's neither young, nor a protocluster, nor still in the process of formation.

If they look really hard (1)

Anonymous Coward | about 2 years ago | (#39918243)

They might be able to find the Destiny.

Now or then? (5, Funny)

Zharr (879496) | about 2 years ago | (#39918485)

To paraphrase: Astronomer: What am I looking at? When does this happen in the Big Bang? Telescope Operator: Now. You're looking at now, sir. Everything that happens now, is happening now. Astronomer: What happened to then? Telescope Operator: We passed then. Astronomer: When? Telescope Operator: Just now. We're at now now. Astronomer: Go back to then. Telescope Operator: When? Astronomer: Now. Telescope Operator: Now? Astronomer: Now. Telescope Operator: I can't. Astronomer: Why? Telescope Operator: We missed it. Astronomer: When? Telescope Operator: Just now. Astronomer: When will then be now? Telescope Operator: Soon.

But, we weren't so far away 12 Billion years ago (3, Insightful)

JSBiff (87824) | about 2 years ago | (#39918585)

Whenever one of these astronomy articles comes up about seeing a galaxy or cluster "near the big bang", there's one fundamental question which has always bothered me. . .

We are told that the universe is expanding, and has been expanding for about 14 Billion years. This means that everything was much closer together back 13 Billion years ago (when the summary says we are seeing the light from). Also, light travels much faster than the universe expands. So. . . why didn't the light pass us billions of years ago?

I realize that light takes time to travel, and that's the idea behind the idea that we can "look back in time" when we look at very distant astronomical objects. . . but. . . again, why didn't the light PASS US billions of years ago, since light expands outward faster than the universe expands outward? Wouldn't the universe need to have been expanding at almost the speed of light, for us to just now receive light from 13 Bn years ago? Well, that is, that the expansion would have had to happen at about 13/14 C?

Re:But, we weren't so far away 12 Billion years ag (2)

Endlisnis (208453) | about 2 years ago | (#39918757)

The universe is expanding at the exact speed of light at it's "edge" (at least the edge we can just barely not see). It's expansion appears to slow on objects closer to us. So this light has been trying to travel across space as it was expanding. The distances it had to travel kept expanding and it eventually reached us after traveling for 12.7B light years (from our perspective).

Re:But, we weren't so far away 12 Billion years ag (2, Informative)

Anonymous Coward | about 2 years ago | (#39920317)

A quick answer is to say that the universe assuredly is expanding faster than the speed of light. Or rather, it's expanding at some rate, and two sufficiently distant points will be receding from one another at the speed of light, or even greater than the speed of light. (You've no doubt heard that "nothing can travel faster than c" but in fact it's really that "energy (hence information) cannot propagate faster than c"... according to relativity spacetime itself can expand at any speed.)

A more detailed explanation can be found by reading this [arxiv.org]. The take-home message is that it's not so intuitive to think about time and distances when spacetime itself is changing as a function of time. Let's say a star is 1 billion light-years (Gly) from Earth. It emits light, and the light travels towards Earth. But since the space in between is expanding while the light is travelling, it will take more than 1 billion years for the light to reach us. And when it does, the star will no longer be 1 billion light-years away, but will be some further distance.

If you look at Figure 1 in the link above, you'll see that what happened is this:

1. When the universe was 1 billion years old, the protocluster emits some light. At this time, the distance from the cluster to Earth (actually, the position where Earth will one day form) is ~2.5 billion light-years.
2. The light travelled outwards, while the universe was expanding.
3. In the present day (age of universe: 13.7 billion years), the light reaches our location. The protocluster (which has now evolved into something else, no doubt) is now at a distance of ~27 billion light-years from us. (Note that currently the edge of the visible universe is ~46 billion light-years away. The universe is only 13.7 billion years old, but the edge is further than 13.7 billion light-years away since, again, that space is moving away from us for that whole time. C.f. comoving distance [wikipedia.org].)

Just More Evidence (-1, Flamebait)

tobiah (308208) | about 2 years ago | (#39918943)

That's just more evidence that there was no big bang. They are too well formed and close together to support the BB hypothesis, and so they disprove it. Next someone will have to invent special undetectable dark waves to explain the discrepancy, and then we can all go on merrily enjoying our latest creation myth.

Re:Just More Evidence (2)

MightyMartian (840721) | about 2 years ago | (#39919047)

It's always fun to watch pseudo-critical morons dance their little dance. How, pray tell, does any of this cause problems for Big Bang cosmology?

Re:Just More Evidence (1)

tobiah (308208) | about 2 years ago | (#39919373)

Ask me politely and perhaps I will explain it to you. Either that or you could read the post you are replying to.

Re:Just More Evidence (3)

MightyMartian (840721) | about 2 years ago | (#39919665)

The post I replied to was written by a moron who uses words he does not understand to make points he cannot support. If you have the words of someone who isn't a moron, then by all means provide them. This is my official "Not Polite To Worthless Fucktards Day", and you sir, qualify, with pathetic idiotic claims that you have somehow debunked Big Bang cosmology.

Re:Just More Evidence (1)

ScentCone (795499) | about 2 years ago | (#39919739)

Why should he have to ask you any more politely than he already did? Your assertion, to which is responded, was clearly intended as a troll, and he called you on it. Trolls don't get polite.

Re:Just More Evidence (1)

tobiah (308208) | about 2 years ago | (#39920395)

As I remain polite, I have either refuted your assertion that my post was trollish or the assertion that trolls don't get polite. If you need a longer explanation try reading this book: http://www.amazon.com/The-Big-Bang-Never-Happened/dp/067974049X [amazon.com]
It is heavily referenced, and much more evidence disproving the Big Bang has appeared since it was written. I don't feel strongly enough to fight about it, but I'm always up for some reasoned discourse. It doesn't have to be polite, so long as it does not confuse a good insult with a good argument. I made a good argument and it has not been addressed.

Re:Just More Evidence (1)

ScentCone (795499) | about 2 years ago | (#39920787)

I made a good argument and it has not been addressed.

Well, you said some stuff. It wasn't a good argument. I could say that the universe was turtles all the way down, and also say that was a good argument. But neither of those things would be true, either.

Re:Just More Evidence (1)

tobiah (308208) | about 2 years ago | (#39921685)

Instead cosmologists are claiming it is 90% super-special undetectable matter and energy. At least the turtle hypothesis is testable.
The Big Bang hypothesis is testable too; it predicts that there were no galaxy clusters 1 billion years (12.7b years ago) after the big bang, it was a bunch of plasma and quasars. And anything observed from that timeframe should look much different than what is next door. So they invent a host of exotic theoretical energies to bring empirical knowledge in line with their theoretically derived origin of the universe.

Re:Just More Evidence (0)

Anonymous Coward | about 2 years ago | (#39922249)

The only problem is that plasma cosmology has been pretty much abandoned ever since WMAP confirmed many predictions about the BB model.

timeline is totally wrong! (2)

sraak (557865) | about 2 years ago | (#39919207)

"..... distance of 12.7 billion light years. "
If an object is 12.7 billion light years from us, the time that light takes to travel to us takes.... 12.7 billion years.

" ...the cluster must still be in the process of formation."
Nope. It _was_ in the process of formation about 12.7 billion years ago. Now that said cluster is 12.7 billion years older, and it is either very old or blown away to bits and pieces some time ago.

The distance works like a time machine, and for example we see and experience our Sun about 8 minutes 11 seconds later, which is the distance between Earth and Sun in "lightyears".

Re:timeline is totally wrong! (0)

Anonymous Coward | about 2 years ago | (#39920439)

Why does one Slashtard have to go on their spiel every single time the term 'light year' is mentioned? This isn't 8th grade earth and space science. We all understand the implications of the time it take light for going from point A to point B. Please just let it go.

Re:timeline is totally wrong! (1)

slew (2918) | about 2 years ago | (#39921161)

Although I'm sure that many introductory physics students might love it if somehow time was somehow independent of distance so you could just easily convert light-years to distance, but it is not. As explained by numerous posters on this thread, there are a couple of big issues with this simplification.

First, the distance to the clusters in question is infered from its red-shift (which it gets from the actual fabric of space itself expanding). The actual paper implies the cluster is approximatly z=6 (where z = (wavelength_observed-wavelength_theory)/wavelength_theory). Using some typical cosmological constants, we can estimate the approximate age *after* the big bang, and our current estimated age and figure out how long ago the light would have taken to get here relative to our reference frame and come up with a "distance of 12.7 billion light years". Ignoring other issues, this can imply that the cluster was actually closer to us than 12.7 billion light years distant when the light was emitted or farther away, but this ignores the expansion of the universe itself which makes this distance vary over time (in a currently unknown way, but distance is assumed to be accellerating over time).

Second, the concept of "now" is not absolute, but depends on the observer's reference frame. The concept of "now" for an object travelling at the speed of light (like a photon which left this cluster) is literally always just now (effectively infinite time dilation) means from the photon's reference frame, things that happened at the cluster when the photon left and here on earth as I am typing are happening simultaneously (from the photon's point of view, it just left the cluster). From the earth's reference frame, things that are happening on earth (like my typing) are not happening simultaneous with when the photon left and to other observers travelling at different velocities (say a person travelling to the cluster from earth), now to us isn't now to them or now to the cluster either.

A curiosity that happens because of this is a close relative to the so-called "twin-paradox" issue. If from the photon's point of view, it just left the cluster, if we somehow turn-it-around and send it back to the cluster, to an observer at the cluster when it "just arrives", the photon will think it has just left, but how long will have elapsed since the first photon left from the cluster's point of view In many respects, this two-way communication is the true time-machine distance operation, not the one-way description in your post, but it too is complicated by the expansion of the universe.

So although in principle, the cluster that we are receiving the light from right now is certainly *older* than when it left, the age that it is *now* is wholy dependent on the observer's frame of reference and complicated by the expansion of the universe.

Kinda makes your head hurt when you think about it.

Nice title... (1)

billybob_jcv (967047) | about 2 years ago | (#39919453)

"Astronomers Find Most Distant Protocluster of Galaxies" - seems to imply a finite universe. That probably makes half the physicists in the world happy...

Re:Nice title... (1)

_0xd0ad (1974778) | about 2 years ago | (#39919539)

Yes, well, whether or not the universe is finite, the headline certainly was, and some things didn't fit.

The summary clarified: "This is the most distant cluster ever seen that has been confirmed spectroscopically."

Big Bang == Creationism For Nerds (0)

Anonymous Coward | about 2 years ago | (#39920465)

If you back away and look at it objectively, the Big Bang Theory is simply a retelling of the Genesis bullshit story, but replacing the names of characters with names that sound less Harry Potterish. Take a good look at it, and forget, if you're capable of it, the utterly false, and intellectually void argument that we must accept it if we cannot ourselves come up with a better theory. Incidentally, I have a better theory, one that accommodates all the "evidence" for the alleged "Big Bang" without resorting to suspending the laws of physics or causality... but last time I discussed it on /., you guys proved you don't like hearing ideas that challenge your cherished fucking illusions, so I'm not going to bother telling you again what happened; apparently, you can't handle the truth. (My view does not require imaginary fairy-tale beings, or they're rebadged pseudo-scientific equivalents.) Enjoy believing in your young-universe cosmology, just don't get mad when my previous predictions come true, and "scientists" and "astronomers" have to keep revising the age of the universe UP as they see things farther and farther away with their ever-increasingly-powerful telescopes...

Re:Big Bang == Creationism For Nerds (1)

tobiah (308208) | about 2 years ago | (#39921775)

So the main piece of evidence for the Big Bang remains redshift of distant galaxies coupled with the assumption that the further away things are the faster they are moving, as opposed to the assumption that light frequency could decline at a very slow and predictable rate. What's your theory on that?

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