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Posted: Wed Feb 13, 2008 10:07 am
by BingoTheClowno
Awesome! Thanks!
NASA wrote:
A massive cluster of yellowish galaxies is seemingly caught in a spider web of eerily distorted background galaxies in the left-hand image, taken with the Advanced Camera for Surveys (ACS) aboard NASA's Hubble Space Telescope.
The gravity of the cluster's trillion stars acts as a cosmic "zoom lens," bending and magnifying the light of the galaxies located far behind it, a technique called gravitational lensing. The faraway galaxies appear in the Hubble image as arc-shaped objects around the cluster, named Abell 1689. The increased magnification allows astronomers to study remote galaxies in greater detail.
One galaxy is so far away, however, it does not show up in the visible-light image taken with ACS [top, right], because its light is stretched to invisible infrared wavelengths by the universe's expansion.
Astronomers used Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) and NASA's Spitzer Space Telescope with its Infrared Array Camera (IRAC) — with help from the gravitational lensing cluster — to see the faraway galaxy.
The distant galaxy, dubbed A1689-zD1, appears as a grayish-white smudge in the close- up view taken with Hubble's NICMOS [center, right], and as a whitish blob in the Spitzer IRAC close-up view [bottom, right]. The galaxy is brimming with star birth. Hubble and Spitzer worked together to show that it is one of the youngest galaxies ever discovered. Astronomers estimate that the galaxy is 12.8 billion light-years away. Abell 1689 is 2.2 billion light-years away.
A1689-zD1 was born during the middle of the "dark ages," a period in the early universe when the first stars and galaxies were just beginning to burst to life. The dark ages lasted from about 400,000 to roughly a billion years after the Big Bang. Astronomers think that A1689-zD1 was one of the galaxies that helped end the dark ages.
The ACS images were taken in 2002, the NICMOS images in 2005 and 2007, and the Spitzer IRAC images in 2006.
Posted: Wed Feb 13, 2008 1:45 pm
by BingoTheClowno
Which you don't believe is true, right?
Posted: Wed Feb 13, 2008 4:10 pm
by BingoTheClowno
stardust wrote:
Reality bites.
Who?
Posted: Wed Feb 13, 2008 4:13 pm
by garyb
everyone.
be careful.
Posted: Wed Feb 13, 2008 4:16 pm
by hubird
fascinating stuff, 'gravitational lensing'.
when can we expect to see the birth of our universe happening back in time?
Posted: Wed Feb 13, 2008 4:23 pm
by BingoTheClowno
hubird wrote:fascinating stuff, 'gravitational lensing'.
when can we expect to see the birth of our universe happening back in time?
Never!
The light could not have escaped the gravitational force.
You didn't read the quote:
NASA wrote:
Astronomers think that A1689-zD1 was one of the galaxies that helped end the dark ages.
Posted: Wed Feb 13, 2008 4:32 pm
by hubird
I did read that, the question then rises did you read this one:
Current theory holds that the dark ages began about 400,000 years after the Big Bang, as matter in the expanding universe cooled and formed clouds of cold hydrogen.
Posted: Wed Feb 13, 2008 4:55 pm
by BingoTheClowno
Yes, I've read it. What does it mean?
Posted: Wed Feb 13, 2008 4:56 pm
by hubird
that there was light (heat) to some degree before the dark ages...as matter is said to have been cooled down.
I don't know anything about the subject tho, but I can read
Posted: Wed Feb 13, 2008 5:12 pm
by BingoTheClowno
Heat doesn't necessarily imply light.
Posted: Wed Feb 13, 2008 5:17 pm
by hubird
what was the supposed temperature 'shortly' after the Big Bang, according to the current state of scientific agreement?
must have been warm at the time:
http://www.astro.ucla.edu/~wright/BBhistory.html
'Universe grows and cools until 100 seconds after the Big Bang. The temperature is 1 billion degrees'
Posted: Wed Feb 13, 2008 5:39 pm
by BingoTheClowno
A billion Kelvin.
Posted: Wed Feb 13, 2008 6:06 pm
by hubird
yes, sorry, the quote ended this way: < , 109 K. >
there must have been quite some light then, and as the universe was expanding, light travelled with it I guess.
But again, I don't know anything about the subject, I'm just intrigued by it
Posted: Thu Feb 14, 2008 9:59 am
by BingoTheClowno
The expansion happened at a much higher speed than the speed of light. It is the only known speed faster than the speed of light. The photons in that era were scattered and bound to other particles. Thus yes, they traveled with the expansion until the atoms started to form. That is the earliest "image" that we can get (300,000 years after BB), which now is severely shifted up in the spectrum, and it called Cosmic Microwave Background radiation. That's the white noise you see on your TV when you tune into an empty channel.
Posted: Thu Feb 14, 2008 12:53 pm
by hubird
I see.
Funny idea to see the BB on tellie
thanks
Posted: Thu Feb 14, 2008 4:17 pm
by BingoTheClowno
stardust wrote: and there was light all the time. Photons of all kind.
But there was no eye to see it.
There was actually
no space for eye to see it...
PS Theoreticaly there wasn't light all the time. There was the quark epoch, hadron epoch etc, when photons didn't exists.
Posted: Thu Feb 14, 2008 10:19 pm
by hubird
I hoped for one single small eye after say 50.000 years
