1639-1710

German astronomer among the first to systematically search the heavens telescopically. He observed sunspots, eclipses, the 1701 Mercury transit, and discovered several comets as well as the variable star chi Cygni (1685). Kirch computed calendars and a well-known set of ephemerides, based on Kepler's Rudolpine tables, for the years 1681-1702. He also designed a new circular micrometer and was appointed the first director of the Berlin Observatory (1700), which was not completed until after his death.