The Gemini Guidance Computer (sometimes Gemini Spacecraft On-Board Computer (OBC)) was a

digital Digital usually refers to something using discrete digits, often binary digits. Technology and computing Hardware *Digital electronics, electronic circuits which operate using digital signals **Digital camera, which captures and stores digital i ...

serial computer A serial computer is a computer typified by bit-serial architecture i.e., internally operating on one bit or digit for each clock cycle. Machines with serial main storage devices such as acoustic or magnetostrictive delay lines and rotating m ...

designed for

Project Gemini Project Gemini () was NASA's second human spaceflight program. Conducted between projects Mercury and Apollo, Gemini started in 1961 and concluded in 1966. The Gemini spacecraft carried a two-astronaut crew. Ten Gemini crews and 16 individual ...

, America's second human spaceflight project. The computer, which facilitated the control of mission maneuvers, was designed by the

IBM Federal Systems Division International Business Machines (IBM), nicknamed "Big Blue", is a multinational computer technology and IT consulting corporation headquartered in Armonk, New York, United States. IBM originated from the unification of several companies that wo ...

.8. J. C. Hundley and R. A. Watson, "A Digital Computer in Orbital Flight," TR 63-825-892, IBM Federal Systems Division, Owego, New York, October 1964.

Functionality

was the first with an on-board computer, as

Project Mercury Project Mercury was the first human spaceflight program of the United States, running from 1958 through 1963. An early highlight of the Space Race, its goal was to put a man into Earth orbit and return him safely, ideally before the Soviet U ...

was controlled by computers on Earth. The Gemini Guidance Computer was responsible for the following functions:McDonnell Corporation, NASA Project Gemini Familiarization Manual, 1965, vol. 2, pp. 8.7,8.45. * ''Ascent ''– serves as a backup

guidance system A guidance system is a virtual or physical device, or a group of devices implement