Cape Astronomical Observatory

(Royal Observatory at the Cape of Good Hope), a scientific establishment of Great Britain, located 5 km from Cape Town (Republic of South Africa). It was founded in 1820 and modeled on the Greenwich Observatory, with which it has been formally united since 1960.

Between 1879 and 1907, the observatory was expanded and reequipped. Its instruments include a triple equatorial telescope with a 61-cm photographic and 46-cm and 20-cm visual objectives, a 33-cm astrograph with a 25-cm guider, a 15-cm visual refractor, 102-cm and 46-cm reflectors, a 10-cm heliograph, a13-cm chromospheric flare patrol, a transit circle, an impersonal prismatic astrolabe, and a cinetheodolite. The observatory is primarily involved in the determination of the precise coordinates, parallaxes, proper motions, and radial velocities of stars; stellar photometry and colorimetry; time service; and solar service. It publishes Anuales (since 1886).