ABSTRACT
Astrobiology is the baseline for the study of possible life forms on exoplanets. It is an emerging multidisciplinary branch involved with the search for extraterrestrial life forms. This chapter gives an exhaustive list of microorganisms tested in outer space. It details several proxy habitability models to understand an exoplanet’s ability to support life of a particular form. At the end of the chapter the readers will find a set of thought provoking scientific queries.
