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Surprise Galaxies at the Edge of Observable Space
brindafella writes "A scientist at the Australian National University's Mount Stromlo & Siding Springs Observatories, Dr Paul Francis, has dicovered a string of galaxies 300 light years long, and further out than they 'should' be. The team were refused time on a US telescope because many American astronomers believed the observations were technically impossible. The findings have been presented at the American Astronomical Society meeting in Atlanta. 'We have detected 37 galaxies and one quasar in the string, but it probably contains many thousands of galaxies.' He said the galaxy string lay 10,800 million light-years away. See the animation here."
Much better luck loading with the story at NASA's site, including an MPEG version of the animation.
I watched C-beams glitter in the dark near the Tannhauser gate.
The team were refused time on a US telescope because many American astronomers believed the observations were technically impossible
This is just sad. I sometimes think we'd be centuries ahead in science if theorists could lay aside their egos and realize that hardly any theory lasts forever in its entirety. Refusing time to a group of astronomers who think they may have found something new is not so different from burning heretics who claimed the world was a sphere.
Maybe overdramatic, but my point stands.
Yeah, it's actually 300 million light-years long. :) Kids these days and their new math.
I watched C-beams glitter in the dark near the Tannhauser gate.
should be the MOST CHAOTIC, not the most ORGANIZED, as they apparently are (being in string formation).
Actually, you're messing up what chaotic means in this case. A string formation may or may not be chaotic, depending on the creation mechanism. In the early days of the Universe, matter would be uniform, not "chaotic". If it was formed as a string, then this would be consistent with an early age, because it hadn't had time for their peculiar velocities to distort the formation. If they didn't form as a string, then it wouldn't be consistent with an early age, because gravity wouldn't've had time to pull them into that shape (assuming it could).
The light that's coming from the farthest away from us is uniform - we call it the Cosmic Microwave Background Radiation. And, amazingly enough, it's incredibly uniform and isotropic. Anisotropies in the CMBR are incredibly small.
If you doubt the Big Bang, get a microwave telescope and look around you. If a Big Bang didn't happen, SOME gigantic, uniform explosion happened, because there's this gigantic, uniform explosion everywhere around you. And it's redshifted by something like z = 10,000 : around 100,000 years after the Big Bang, if my memory serves. That is the universe, as it was very, very close to the Big Bang.
This observation just shows that galaxies formed quicker and faster than theorists predicted. This is not a big deal.
After all, theorists for a while had a hard time explaining how galaxies formed at all. The string formation may suggest that cosmic strings (1-dimensional topological defects) may actually have existed in the early universe. Cosmic strings have been "down on their luck" theoretically recently, as the preponderance of dark matter and energy have convinced many people you don't actually need cosmic strings. This may start them thinking otherwise.
"faith" to believe that that universe was created by chance than it does to believe that SOME outside, intelligent force "caused" it to be (the details of which are certainly open to debate).
Chance has a perspective issue. Saying something happened by "chance" and saying that it was "planned" is a matter of belief, not of fact. Nowhere do scientists say why something happened. Just how. Trying to use scientific arguments to justify a "why" is flat wrong - you're trying to justify a statement that requires evidence outside of a proper frame of reference. It's similar to the problems with the strong anthropic principle - fundamentally, from our point of view, it's indistiguishable from its opposite (oddly enough, because of the weak anthropic principle). You can't tell the difference between a "chance" creation or a "designed" creation by an intelligent force because they produce exactly the same results, because fundamentally, you have to produce a universe capable of having humans (the weak anthropic principle). We have no knowledge of the number of "dead" universes, nor whether or not "dead" universes could even exist. Therefore, from our point of view, there's no way to prove which is correct, and which is incorrect, and therefore, it's a matter of belief, not of science.
> This surprise has nothing to do with distance from the "center" of the big bang,
> since there is no center
I've heard this before, and although I don't disagree with it, I've never been able to wrap my brain around it. It seems to me that any explosion has a center, or a point of origin. Even one that expands out into "nothing" like the Big Bang did/is.
This is, unfortunately, a flaw in the name of the model. It conjures up the idea of an explosion of material into surrounding empty space, which is not what the Big Bang model describes. The expansion of the Universe is an expansion of space itself. The galaxies grow farther apart not because they are moving away from each other through space, but because space itself is expanding between them.
Not that that necessarily makes things easier for you. Fundamentally, this points out a failure of one of our most useful way of understanding thimgs: to relate them to things we already understand, or with which we are already familiar. For instance, when authors of cosmology books for laypersons construct analogies to the expansion of space and the resulting increasing separation of the galaxies, they use things like a loaf of raisin bread expanding in the oven. But that analogy is flawed: the raisin bread has space surrounding it into which it can expand (not to mention a "center"), while no such thing exists for the universe.
A better analogy in that it gets rid of the embedded center is to give up our 3D universe, and instead consider the 2D surface of an inflating balloon. Dots (galaxies) painted on the balloon's surface are all getting farther and farther apart from each other on the surface of the balloon (in space), but no place on the surface of the balloon (no location in the Universe) can be called the center of the expansion (the one place from which things started expanding apart). But this analogy is a bad one, as well. It makes an assumption about the topology of the universe (that it loops around on itself, or is "closed"); the Universe may be that way, but it need not be. More importantly, this analogy requires the existence of a 3rd dimension (the radial direction) separate from the 2D surface of the balloon; a change in the position of the surface of the balloon with time in that radial direction describes the expansion. But the Big Bang model doesn't require such a hidden dimension which is driving the expansion.
There just isn't something from our day-to-day lives which provides a decent analogy to the expansion of the Universe. It has to be understood on its own terms, without recourse to simple visualization. Not that this is uncommon in physics since the beginning of the 20th Century; for instance, quantum mechanics describes phenomena which are difficult to impossible to describe in terms of how things work in our common sense, everyday world. In the end, it comes down to a quote from (I think) Feynman (although he was talking about quantum mechanics at the time): "I don't know how to describe it in terms of something you're more familiar with, because I don't understand it in terms of something you're more familiar with."