Van Biesbroeck 8 (vB 8, Gliese 644 C) is a low-luminosity star in the constellation Ophiuchus, cataloged in the 20th century (in 1961) by the astronomer George Van Biesbroeck. It is the smallest, faintest, and most separated component of the quintuple star system Gliese 644/643 — the richest stellar system in the immediate solar neighbourhood (d<10pc). Classified as a red dwarf star, it is approximately 18.7 light years from our solar system and possesses about 9% of the mass of the Sun. In 1984, apparently erroneous information led to the belief that the first extra-solar "planet" (later deemed to possibly be a brown dwarf) was orbiting Van Biewsbroeck 8. The object, termed Van Biesbroeck 8b, was twice confirmed, but subsequent attempts to locate it were unsuccessful.