Stephen C. Singer-Brewster (b. 1945) also known as Stephen C. Brewster is an American astronomer. He is a member of the American Association of Variable Star Observers. He participated in the Palomar Planet Crossing Asteroid Survey (PCAS) as an observer and astrometrist under the direction of American astronomer Eleanor Helin (JPL/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.