Astrobiology is the study of the origins, evolution, distribution, and future of life in the universe. This interdisciplinary field requires a comprehensive, integrated understanding of biological, planetary, and cosmic phenomena. Astrobiology encompasses the search for habitable environments in our Solar System and on planets around other stars; the search for evidence of prebiotic chemistry or life on Solar System bodies like Mars, Jupiter’s moon Europa, and Saturn’s moon Titan; and research into the origins, early evolution, and diversity of life on Earth.
The field of astrobiology is relatively new when compared to the long established fields of astronomy, biology, physics, geology, planetary science, etc. At this time, there are very few dedicated degree programs in astrobiology. The typical pathway for a student interested in pursuing astrobiology graduate studies is to specialize in a single scientific discipline. You should choose a field that really excites you. This discipline will be the base of knowledge that you will build upon, so make it one you are passionate about.