Dear MEL
Topic Readers,
The fact the
sky is dark reveals a lot about the Universe
The sky is
blue in the daytime, provided that there are no clouds over you. Likewise, the
sky is dark at night, unless a supermoon reflects the sunlight brightly. You
know that, but have you ever questioned yourself, or someone else, why the sky
is dark at night?
Though there
are hundreds of billions of live stars shining in the universe, they don’t seem
to be bright enough to make the universe white or even gray. You might think
that those stars are too far away from Earth. Yes, indeed. The age of the light
from a star could be as old as 13.7 billion years because it was the time when the
universe was born, the Big Bang. But the lights that reach Earth might have
travelled even longer light years because the universe is still expanding
faster than the speed of light. It sounds too dim for any light to brighten
this dark universe, doesn’t it?
Enjoy seeing
this animation video to learn about stars and universe.
If you are
also interested in why the sky is blue question, check this out.
http://www.todayifoundout.com/index.php/2010/05/why-the-sky-is-blue/
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