https://www.youtube.com/watch?v=oOCBGisXXDo&feature=share

How do we find other planets?
For life in the universe to be abundant, planets must be abundant. But planets are hard to detect because they are small, and much fainter than the stars they orbit.

How does life begin?
Scientists do not yet know how the first living things arose on Earth. The geological record shows that life appeared on Earth almost as soon as the young planet was cool and stable enough for living things to survive. This suggests that life may exist wherever conditions allow it.