55 Cancri is a double star that consists of a yellow main sequence dwarf belonging to the spectral class G8V and a 13th magnitude red dwarf that can only be seen through a telescope. The system is approximately 41 light years distant.
55 Cancri is notable because, as of 2010, astronomers have confirmed five extrasolar planets orbiting the primary star in the system, 55 Cancri A. This is one of the four known planetary systems known to have at least five planets. (Others are our solar system, Gliese 581 in the constellation Libra and HD 10180 in Hydrus.) The planet nearest to the star is believed to be a terrestrial planet with a mass similar to Neptune, while the outermost planets are believed to be Jovian planets, with masses comparable to that of Jupiter.