Career
He participated in the Palomar Planet Crossing Asteroid Survey (PCAS) as an observer and astrometrist under the direction of American female astronomer Eleanor Helin (Jet Propulsion Laboratory/Caltech) from 1985 to 1988. During this period, Stephen Brewster was credited with the discovery of 105P/Singer Brewster, a Jupiter-family comet. He also discovered six asteroids including the named main-belt asteroid 4555 Josefapérez and 5253 Fredclifford, a Mars-crosser.
He formed the Faint Object Follow Up (FOFU) project at Stony Ridge in 2000 to encourage observations of faint asteroids and comets.
Eleanor Helin honored him with the naming of the asteroid 10315 Brewster, to acknowledge his work for PCAS, Stony Ridge Observatory, and the Jet Propulsion Laboratory (Jet Propulsion Laboratory). At Jet Propulsion Laboratory, he worked on a number of spacecraft missions such as the Pluto Fast Flyby, the Outer Planets/Solar Probe Mission and the Europa Orbiter mission.
At the time of his retirement in 2003 he was working in the Mars Advanced Studies Program and the Europa Orbiter/X2000 avionics development project at Jet Propulsion Laboratory.