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The Earth and Beyond

The Universe - Big Bang.

The "big bang" is the most widely accepted theory
explaining how the Universe began.

The theory suggests that a long time ago (about 15 billion years)
the Universe started as a big explosion.
All the energy and matter which exists today came from this original explosion.

The evidence for this theory comes from two observations.
1.  Light from stars in other galaxies is red-shifted.
2.  There is background microwave radiation everywhere in space.

You don't need to be able to explain the background microwave radiation,
just know that it exists.
Clever scientists did some mathematical calculations
on what would have happened in the big bang.
Their calculations showed that there should be
a low level of microwave radiation as a result of the original explosion.
When they looked out into space
 they found this background microwave radiation everywhere.

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Copyright © 2008 Dr. Colin France. All Rights Reserved.