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Astronomy Picture of the Day -- A Redshift Lookup Table for our Universe
NASA ^ | April 08, 2013 | (see photo credit)

Posted on 04/08/2013 3:19:22 AM PDT by SunkenCiv

Explanation: How far away is "redshift six"? Although humans are inherently familiar with distance and time, what is actually measured for astronomical objects is redshift, a color displacement that depends on exactly how energy density has evolved in our universe. Now since cosmological measurements in recent years have led to a concordance on what energy forms pervade our universe, it is now possible to make a simple table relating observed cosmological redshift, labeled "z", with standard concepts of distance and time, including the extrapolated time since the universe began. One such table is listed above, where redshift z is listed in the first and last columns, while the corresponding universe age in billions of years is listed in the central column. To find the meaning of the rest of the columns, please read the accompanying technical paper. Although stars in our galaxy are effectively at cosmological redshift zero, the most distant supernovae seen occur out past redshift one, which the above chart shows occurred when the universe was approximately half its present age. By contrast, the most distant gamma-ray bursts yet observed occur out past redshift six, occurring when the universe was younger than one billion years old, less than 10 percent of its present age.

April 08, 2013

(Excerpt) Read more at 129.164.179.22 ...


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; astronomy; redshift; science
[Credit: Sergey V. Pilipenko (LPI, MIPT)]

1 posted on 04/08/2013 3:19:22 AM PDT by SunkenCiv
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To: brytlea; cripplecreek; decimon; bigheadfred; KoRn; Grammy; married21; steelyourfaith; Mmogamer; ...

2 posted on 04/08/2013 3:19:50 AM PDT by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: SunkenCiv
accompanying technical paper, btw.
3 posted on 04/08/2013 3:41:16 AM PDT by Telepathic Intruder (The only thing the Left has learned from the failures of socialism is not to call it that)
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To: SunkenCiv

Great find, thanks!


4 posted on 04/08/2013 6:09:55 AM PDT by Graewoulf (Traitor John Roberts' Commune-Style Obama'care' violates U.S. Constitution AND Anti-Trust Law.)
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