Galaxy from 700 million year old universe

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A recently reported galaxy, possibly the earliest observed, has a redshift of 7.6, indicating its light has traveled 12.9 billion years, originating when the universe was only 700 million years old. Calculations show its recession speed was 3.3 times the speed of light when the light was emitted, and it is currently receding at 2.1 times the speed of light. The galaxy was approximately 3.4 billion light-years away at the time of emission, and now it is about 29.4 billion light-years distant. Gravitational lensing by a foreground galaxy has magnified this observation, and the upcoming James Webb telescope is expected to provide further insights into this ancient galaxy. This discovery highlights the advancements in astronomical technology and the potential for future exploration of the universe's early history.
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One of the earliest, maybe the earliest galaxies seen so far.
Redshift 7.6 reported at conference. If confirmed then the light from it has been traveling some 12.9 billion years and was emitted when expansion was only about 700 million years old.
Put 7.6 into either of these calculators to get distances and recession speeds
Ned Wright's
http://www.astro.ucla.edu/~wright/CosmoCalc.html
just plug in 7.6 for z, over on the left

Ned Wright puts in the default values of H=71, and Omega_matter = 0.27 and Lambda = 0.73. they are accepted parameter values, widely used. With Morgan's calculator you have to type in those three parameter values
http://www.uni.edu/morgans/ajjar/Cosmology/cosmos.html
Over on the left, put in 0.27 for matter, 0.73 for Lambda, and 71 for Hubble.

Here is a press release about it, and a blog report from the conference:
http://hubblesite.org/newscenter/archive/releases/2008/08/full/
http://scienceblogs.com/catdynamics/2008/02/liveblogging_the_high_redshift_1.php

Larry Bradley, Garth Illingworth, Rychard Bouwens are some names to search on, to find out more.
They had 10X gravitational lensing magnification by a galaxy in the foreground. The James Webb telescope (launch 2013?) will be able to see detail in this young galaxy.

The recession speed was 3.3c THEN when it emitted the light we are now receiving from it, and its recession speed now is 2.1c
(you can check this with Morgan's calculator if you wish)
When it emitted the light it was about 3.4 billion lightyears from us. And today, as we are receiving the light, it is about 29.4 billion lightyears from us.

the ratio of those two distances should be 1+z = 8.6 because that is the factor by which distances have grown during the time the light has been in transit.
 
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Wow, that's amazing! It's incredible to think that we can actually see something that is 12.9 billion years old. It's a reminder of just how far our technology has come and what we are capable of. I'm looking forward to the launch of the James Webb telescope and seeing what more we can learn about this distant galaxy!
 
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