The technological marvel that facilitated the Apollo missions to the
Moon was the on-board computer. In the 1960s most computers filled an
entire room, but the spacecraft's computer was required to be compact
and low power. Although people today find it difficult to accept that it
was possible to control a spacecraft using such a 'primitive' computer,
it nevertheless had capabilities that are advanced even by today's
standards.
This is the first book to fully describe the Apollo guidance computer's
architecture, instruction format and programs used by the astronauts. As
a comprehensive account, it will span the disciplines of computer
science, electrical and aerospace engineering. However, it will also be
accessible to the 'space enthusiast'. In short, the intention is for
this to be the definitive account of the Apollo guidance computer.
Frank O'Brien's interest in the Apollo program began as a serious
amateur historian. About 12 years ago, he began performing research and
writing essays for the Apollo Lunar Surface Journal, and the Apollo
Flight Journal. Much of this work centered on his primary interests, the
Apollo Guidance Computer (AGC) and the Lunar Module. These Journals are
generally considered the canonical online reference on the flights to
the Moon. He was then asked to assist the curatorial staff in the
creation of the Cradle of Aviation Museum, on Long Island, New York,
where he helped prepare the Lunar Module simulator, a LM procedure
trainer and an Apollo space suit for display. He regularly lectures on
the Apollo computer and related topics to diverse groups, from NASA's
computer engineering conferences, the IEEE/ACM, computer festivals and
university student groups.
