The most complete biography of Kepler is Max Caspar's Kepler. Though there are a number of more recent biographies, most are based on Caspar's work with minimal original research; much of the information cited from Caspar can also be found in the books by Arthur Koestler, Kitty Ferguson, and James A. Connor. Owen Gingerich's The Eye of Heaven builds on Caspar's work to place Kepler in the broader intellectual context of early-modern astronomy. Many later studies have focused on particular elements of his life and work. Kepler's mathematics, cosmological, philosophical and historical views have been extensively analyzed in books and journal articles, though his astrological work—and its relationship to his astronomy—remains understudied.
