A light-sensitive device that orients a spacecraft towards the Sun. It is part of the attitude control system.
When ‘Sun acquisition’ occurs, the device's sensing voltage changes from low to high. The TOPEX/Poseidon spacecraft, launched on 10 August 1992 to measure ocean surfaces, carried two Sun sensors to ensure that the vehicle's altimeter antenna pointed straight down to the sea.
Subjects: Astronomy and Astrophysics.