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Why is the sky dark at night?

Started by maah, 02/22/2008 08:26PM
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Posted 02/22/2008 08:26PM Opening Post
Magnus Ahrling
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Why is the sky dark at night? There are so many stars and galaxies shining, so they should shine as bright as our Sun does in daytime.
I have read all`bout (well almost!) Olbers Paradox but can`t find the answer.
Can anybody here enlighten me!

Magnus











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Posted 02/22/2008 09:33PM #1
Hugh Bartlett
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The night sky would be as bright as day if the universe had an infinite age. Since the universe has only been in existence for 13.7 billion years, light from some parts of the universe has not had time to reach us yet.

Hugh Bartlett
Oakland, CA
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"Praise the Lord for the expanding grandeur of creation, worlds known and unknown, galaxies beyond galaxies, filling us with awe and challenging our imaginations." 2007 Reform Siddur
Posted 02/22/2008 09:44PM #2
Alan French
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"Darkness at Night (A Riddle of the Universe)," by Edward Harrison. Well worth reading, and probably available at a local library.

Clear skies, Alan
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Posted 02/23/2008 05:42PM #3
Alex McConahay
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If the sky did not get dark at night, there would be no need for daylight savings time.

Alex
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Posted 02/25/2008 07:02AM | Edited 02/25/2008 07:03AM #4
Inge Skauvik
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Sometimes I feel like a grumpy old man, therefore I'm a bit reluctant to give this comment.
In my opinion this thread belongs under the general "Astronomy" forum.

However, since it has been running here for some time, I suggest that you keep on the discussion here.

Inge S
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Posted 02/25/2008 06:38PM #5
john mclaughlin
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I am not sure if this has been mentioned, but wouldn't the sky be bright if Earth was located closer to the center of the galaxy?

John
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Posted 02/26/2008 07:51PM #6
Dave Mitsky
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Magnus,

Here are a few websites to consult:

http://math.ucr.edu/home/baez/physics/Relativity/GR/olbers.html

http://en.wikipedia.org/wiki/Olbers'_paradox

http://www.arachnoid.com/sky/index.html

http://www.faqs.org/faqs/astronomy/faq/part9/section-17.html

Dave Mitsky
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Chance favors the prepared mind.

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