Astrobiology seeks to answer the mysterious question:

Are We Alone?

To do this astrobiologists need to understand:

-The building blocks of life

-How the building blocks combine to create life

-How life is affected by the environment

-How life expands beyond the planet's origin

 

Exobiology is the study of the possibility of life elsewhere in the universe.

For life on another planet to exist the planet has to be close enough to the star to be in the habitable zone around the star.