Upsilon Andromedae

Upsilon Andromedae (υ Andromedae, υ And) is a binary star located approximately 44 light-years away from Earth in the constellation Andromeda. The primary star (Upsilon Andromedae A) is a yellow-white dwarf star that is somewhat younger than the Sun. The second star in the system (Upsilon Andromedae B) is a red dwarf located in a wide orbit.

As of 2010, four confirmed extrasolar planets are known in orbit around the primary star. All four are likely to be jovian planets that are comparable to Jupiter. Upsilon Andromedae was both the first multiple-planet planetary system to be discovered around a main sequence star, and the first multiple-planet system known in a multiple star system. Upsilon Andromedae A was ranked 21st in the list of top 100 target stars for the NASA Terrestrial Planet Finder mission, which has, however, been reported to have been cancelled as of 2011.