Dirty snowball led to life

NASA

NASA's Stardust spacecraft successfully flew through the tail of Comet Wild 2, retrieving a sample of comet dust to be studied here on Earth. After carefully analyzing the space sample, scientists have confirmed that one of the many substances collected is glycine.

This is the first time an amino acid has been found in a comet. Glycine is a key building block of life, used to make proteins. The find supports theories that some ingredients for life on Earth came from space and that other life may be out there.