Pg.+115

1. One observation that supports the big bang theory is that two scientists found radiation coming from everywhere in space, and they said it was cosmic background radiation, which is radiation left over from the big bang.

2. The big bang theory explains the observed expansion of the universe because they realized that the galaxies were moving away from each other and expanding, and then they thought of it backwards, so it was coming together to form a single point. They came up with the big bang theory from this.

3. Since large telescopes gather more light than small telescopes do, large telescopes are used to look at distant galaxies. This is because it makes them easier to see, since they are so far away.