Posted on 02/20/2008 10:32:46 PM PST by neverdem
Using a cosmic magnifying glass to peer into the deepest reaches of space, two teams of astronomers have discovered tiny galaxies that may be among the most distant known. Images suggest that one of the galaxies is so remote that the light now reaching Earth left this starlit body when the 13.7-billion-year-old universe was only about 700 million years old.
The discoveries are important, notes Tim Heckman of Johns Hopkins University in Baltimore, because they probe a special time in the universe, when the cosmos changed from a place filled with neutral gas to a place ionized by the emergence of the first substantial population of stars and black holes. Studies of distant galaxies help pinpoint when that critical era happened.
All of the galaxies are so small that even the keen eye of the Hubble Space Telescope couldn't have spotted them without nature providing a gravitational assist. According to Einstein's theory of general relativity, a massive foreground body acts like a lens, bending and magnifying light from a more remote galaxy that lies along the same line of sight to Earth.
That's why Garth Illingworth and Rychard Bouwens of the University of California, Santa Cruz and their colleagues went hunting for distant galaxies around a nearby cluster of galaxies called Abell 1689.
The cluster's gravity distorts images of background galaxies, bending them into arcs and magnifying their brightness. One of these galaxies proved especially intriguing because it appeared bright at several infrared wavelengths recorded by Hubble but disappeared in visible light.
That's a sign that the galaxy, dubbed A1689-zD1, is both extraordinarily distant and youthful. The data also indicate that the galaxy forms stars at a rate equivalent to five suns a year, typical of the small galaxies thought to be common in the early universe, says Bouwens...
(Excerpt) Read more at sciencenews.org ...
YEC INTREP
Fascinating.
I’ve wondered how long after the almost unimaginable explosion of the big bang enough cooling would occur to allow galaxies.
Apparently no more than 700 million years.
Big Bang, dark matter, black hole, speed of light, what a load of tripe. The emperor has no clothes. The Universe is a waterfall of electromagnetism carried by immense plasma streams that cause our aurora borealis. All the planets have been demonstrated to possess magnetotails, ours is the Van Allen Belt. We are living on a low intensity comet. I can’t believe what I hear orthodox scientists utter any longer.
Space ping
I still can’t wrap my head around galactic distances and times.
I remember something like the “event horizon” ?
Something about a limit beyond which we can’t see back into the early universe..
Ring any bells?
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neverdem - great post. I read this earlier in a shorter article, but your link is much better. Keep the hard science coming. It’s always a nice break from my usual diet of 24-7 politics.
Mommy i’m up way past my bedtime but this is quite fascinating!
You're free to believe what you want. The accuracy of targeting by advanced U.S. military weaponry and global positioning systems depends on the speed of light.
thanks neverdem.
Farthest Galaxy Found, Perhaps
(~13 billion light-years away, Hubble and Spitzer images)
Space.com on Yahoo | 2/12/08 | Clara Moskowitz
Posted on 02/12/2008 3:49:07 PM EST by NormsRevenge
http://www.freerepublic.com/focus/f-chat/1969233/posts
The term event horizon refers to the boundary region around a black hole within which gravity is so strong even light cannot escape. Events within that horizon are thus barred from interacting with events outside it, as no signal can travel outward successfully (up to a quibble about quantum effects right at the boundary).
What you are thinking of is the epoch when the universe became transparent. Originally theory says it was a plasma - like a fireball, all particles "ionized" or in other words stripped of their electrons which fly around free themselves - which would not transmit light, since any photon would collide with something (usually one of the electrons) before getting far, and be scattered again.
That is as far back as one could theoretically "see" in time with "old light", because light earlier than that couldn't travel. Once the universe cools enough that electrons are captured by atoms, it becomes transparent to light, and light emitted from that point on might reach us now, if it started far enough away.
The cosmic microwave background radiation - a diffuse, nearly uniform microwave "hum" seen in all directions, at an absolute temperature of 3 degrees kelvin worth of energy, is thought to be the afterglow of that epoch, or the "first light" that could get to us now. Not that there wasn't any earlier, but it would have been totally scrambled by multiple absorptions and re-emissions (aka collisions or scatterings) in the plasma etc.
This is usually called the epoch of transparency or something similar, but not "event horizon".
700 million years is long after it is thought to have occurred, though.
Thanks very much. Yes, event horizon I definitely confused with black holes.
I understand your explanation on this. I was thinking it was something to do with time/universe rate of expansion/speed of light/our distance...
but I must have been confused there as well.
thank you very much for taking the time to explain this...
Are we talking something out of or into nothing? If the universe is expanding, into what is it expanding?
I thought space was infinite.
Maybe the universe is part of a greater expansion of multiverses, and as this one dissipates, 2 or 3 or 5 new ones will pop up to replace it.
We can measure whether light from distant stars is redshifted or blueshifted, because different atoms emit definite spectral lines in a clear pattern. If you line up the pattern seen in a lab from e.g. glowing hydrogen, with the pattern seen from a distant star, they are the same distance apart and the same line widths, but all moved toward red by the same amount. Ergo, that star is moving away from us, at a velocity we can measure by how much the light-pattern moved.
For nearby objects, some are redshifted and some are blueshifted, because they all have "proper motions" toward or away from us. But go far enough away, and there aren't any objects headed toward us anymore. Everything is receding, and faster and faster the farther it is away.
One might imagine this is because we are smack at the center of everything, and everything is specifically moving away from this one and only spot, at higher and higher speeds, because gosh nothing wants to be here.
But scientists don't accept explanations that "ad hoc". The other possible conclusion is that anywhere you are, you'd see that - because space itself is expanding. That is the current accepted theory, to explain the red shift seen in the color spectra of distant objects.
I hope this helps.
Here is another related one I quite like, from a writer named Harry Mulisch. It is the idea of an "historiscope". Since as we look farther away, we are looking backward in time, the idea is to exploit this to look backward in time right where we are, aka to literally see our own history. All it would require is something shiny and reflective enough at a great enough distance, combined with a powerfully enough telescope to see the reflection.
Imagine a giant mirror 1000 light years away, directly aligned to face us, and a monster telescope array the size of a whole solar system or something similar. Focus the telescope on the mirror. Then the light impacting the telescope this instant, will be photons that left the mirror 1000 years ago. But some of those are photons that left earth 1000 years before *that*, travel to the mirror for a thousand years, hit it and bounced, and have now spent another thousand years on the return journey. So as you looked in the mirror, you would literally see the earth 2000 years ago.
The beautiful thought involved in this is that the past is not gone. Information about it is streaking off into space at the speed of light, and bouncing in ripples off everything it touches, and some of those ripples can come right back here. The past is in principle directly observable. Not just the light years distant, astronomical past, but in principle even local happenings.
Of course the practicalities of actually exploiting this are daunting. Very few photons hit any given object a long way away, most things aren't that shiny and aren't aligned, few of the scattered photons come back to any local detector, etc. But the principle of the thing is still mindblowing, in my humble opinion, and indescribably beautiful.
For what it is worth...
Fascinating....
Cheers!
Should you be interested in REAL science and TRUTH, your local community college will lead you in courses in Physics and Astronomy....of course...you really have to want TRUTH.
As an amature astronomer I run into your kind all the time on the Internet. Its sad that our schools have failed to bring the public up to a level of knowledge that would make clear the difference between Science FACT and science fiction.
Is "universe" and "space" terms for the same thing, or is it the "universe" that is expanding into "space"?
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