Why is it Dark at Night?
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Published on Sep 30, 2012
Have you ever wondered why you look up and see a dark sky at night?
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Music by Nathaniel Schroeder
Thanks to Nima Doroud and Niayesh Afshordi for contributions and to Perimeter Institute for support.
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Top Comments
n00b4liciou5 2 weeks ago
Sometimes, before I fall asleep, I look up at the dark, yet sparkling, sky and wonder: Where the Hell is my ceiling?!
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Stephan de Vries 1 week ago
Now I finally understand how infrared cameras work!
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All Comments (12,249)
damagon123 2 hours ago
Before video: One unanswered question.
After video: 10 unanswered questions.
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Spencer Marfy 6 hours ago
Why is the sky blue?
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carr60ick 7 hours ago
check out the work of walter russell at
w w w d o t walter-russell d o t c o m
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Jude Granada 9 hours ago
so by the time all of the lights in the universe reaches us, is it gonna be bright/ daytime in the entire planet?
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rez tonosaur 10 hours ago
you dont say..???
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baadshepherd 1 day ago
You could see some of the light from it, but the majority of the light from the Big Bang would have spread in different directions, so no, you couldn't see the Big Bang event.
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Jorden Gillespie 1 day ago
I got this one
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Kasper Kivimäki 2 days ago
If we would go in somewhere at the universe, very long away. Then could we see the big bang. Cause isn't some of that light still traveling.
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MrMadr0 2 days ago
Time for us is a linear perception, but time in reality is another dimension of reality, its our perception which gives us the feeling of a forward moving time.
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TFSWOLF 2 days ago
There is no such thing as time. There can not be a "temporal edge" time is an illusion, a human perception. Everything in the universe happens at once. Without time. Its a bit hard to immagine as things can not litterally happen all at once. I cant go watch the earth being destroyed while drinking tea with abraham lincoln. Just immagine that there is no such thing as time and things just happen one way or another.
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