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Going the Distance: Galaxies may hail from early universe
Science News ^ | Week of Feb. 16, 2008 | Ron Cowen

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 ...


TOPICS: Culture/Society; News/Current Events; Technical
KEYWORDS: astronomy; gravitationallensing; hubble; spitzer
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LONG AGO, FAR AWAY. Gravity of the cluster Abell 1689 acts as a gravitational lens, bending into arcs and magnifying the light from remote background galaxies. One galaxy appears so remote that it doesn't show up in visible light (top, right) but only in the infrared (middle and bottom, right).
L. Bradley & H. Ford/JHU, Bouwens & Illingworth/UCSC, NASA, ESA
1 posted on 02/20/2008 10:32:51 PM PST by neverdem
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To: neverdem

YEC INTREP


2 posted on 02/20/2008 10:36:05 PM PST by LiteKeeper (Beware the secularization of America; the Islamization of Eurabia)
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To: neverdem

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.


3 posted on 02/20/2008 10:41:47 PM PST by gondramB (Preach the Gospel at all times, and when necessary, use words.)
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To: neverdem

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.


4 posted on 02/20/2008 10:58:34 PM PST by Yollopoliuhqui
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To: KevinDavis

Space ping


5 posted on 02/20/2008 10:59:50 PM PST by wastedyears (This is my BOOMSTICK)
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To: neverdem

I still can’t wrap my head around galactic distances and times.


6 posted on 02/20/2008 11:07:33 PM PST by wastedyears (This is my BOOMSTICK)
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To: LiteKeeper

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?


7 posted on 02/20/2008 11:33:22 PM PST by D-fendr (Deus non alligatur sacramentis sed nos alligamur.)
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To: El Gato; Ernest_at_the_Beach; Robert A. Cook, PE; lepton; LadyDoc; jb6; tiamat; PGalt; Dianna; ...
Strokes among middle-aged women triple

Math on Display - Visualizations of mathematics create remarkable artwork

Evolutionary History Of SARS Supports Bats As Virus Source

FReepmail me if you want on or off my health and science ping list.

8 posted on 02/20/2008 11:46:49 PM PST by neverdem (I have to hope for a brokered GOP Convention. It can't get any worse.)
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To: neverdem

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.


9 posted on 02/20/2008 11:49:01 PM PST by zeestephen
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To: neverdem

Mommy i’m up way past my bedtime but this is quite fascinating!


10 posted on 02/20/2008 11:49:02 PM PST by poobear (Pure democracy is two wolves and a lamb voting on what's for dinner. God save the Republic!)
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To: Yollopoliuhqui
Big Bang, dark matter, black hole, speed of light, what a load of tripe.

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.

11 posted on 02/20/2008 11:51:48 PM PST by neverdem (I have to hope for a brokered GOP Convention. It can't get any worse.)
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To: neverdem

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


12 posted on 02/20/2008 11:56:09 PM PST by SunkenCiv (https://secure.freerepublic.com/donate/___________________Profile updated Tuesday, February 19, 2008)
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To: D-fendr
No, you are confusing two difference concepts.

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.

13 posted on 02/21/2008 12:04:55 AM PST by JasonC
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To: JasonC

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...


14 posted on 02/21/2008 1:18:11 AM PST by D-fendr (Deus non alligatur sacramentis sed nos alligamur.)
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To: neverdem; JasonC; D-fendr
Thanks for stirring my imagination and intellect with the wonder that completely surrounds us. This is fascinating stuff.
15 posted on 02/21/2008 1:57:32 AM PST by Caipirabob (Communists... Socialists... Democrats...Traitors... Who can tell the difference?)
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To: neverdem

Are we talking something out of or into nothing? If the universe is expanding, into what is it expanding?


16 posted on 02/21/2008 7:08:07 AM PST by AxelPaulsenJr (God Bless George W. Bush)
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To: AxelPaulsenJr
Are we talking something out of or into nothing? If the universe is expanding, into what is it expanding?

I thought space was infinite.

17 posted on 02/21/2008 9:56:48 AM PST by neverdem (I have to hope for a brokered GOP Convention. It can't get any worse.)
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To: AxelPaulsenJr

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.


18 posted on 02/21/2008 10:55:47 AM PST by Stimpson_J_Cat
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To: AxelPaulsenJr
The distance between all objects is increasing with time. The farther apart they are, the faster this "runs". Space itself is expanding. We conclude this because in every direction we look, distance objects are receding from us, which we can tell because the light from them is shifted toward the red end of the spectrum (longer wavelength). This is the same doppler effect that changes the sound pitch as a train goes by - you can tell by the sound difference whether it is approaching or receding.

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.

19 posted on 02/21/2008 9:31:01 PM PST by JasonC
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To: neverdem
Nobody knows, but there is no reason it has to be.
20 posted on 02/21/2008 9:31:39 PM PST by JasonC
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