Page 56 - Curriculum Visions Dynamic Book

 This is a picture of the microwave background radiation for the entire sky as seen from the Earth. Reds show more, blues show less radiation. The fact that the pattern of reds and blues is even across the sky is evidence for microwave background radiation being everywhere. This is the main support for the Big Bang theory.
Once atoms began to form, they could come together to form molecUles. Gravity began to affect the molecules scattered around as gas, drawing them together and forming stars and galaxies, and producing the Universe as we know it today.
How can we support this idea? One way is to look for traces of the first Big Bang. Any explosion causes shock waves. Some are sound waves, some are light waves, and some are other kinds of radiation. These waves remain when the explosion seems to be long over.
Everywhere astronomers look today they find microWave radiation. This is difficult to explain because it is in every part of the Universe. But one explanation for it would be that it is the remains of a once fierce light that accompanied the explosion, and that has now decayed to weak microwave radiation.
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