The Department of Astronomy offers a graduate program aimed at the PhD degree in astrophysics. Entering students need not have majored in astronomy, although some background in astronomy is desirable. A strong background in physics, however, is essential.
Research is a major part of the PhD program, and the department offers opportunities in a wide variety of fields, including theoretical and observational astrophysics; infrared, optical, and radio astronomy; galactic structure and dynamics of stellar systems; high-energy astrophysics and cosmology; and star and planet formation.
Source: Berkeley Academic Guide