The Gliese 581 system is a star system located in the Milky Way Galaxy at about 20.4 light years from planet Earth. It was composed of the Red dwarf Gliese 581 and at least five planets orbiting it. Three of these planets, Gliese 581c, Gliese 581d and Gliese 581g, orbit the star's habitable zone where liquid water could be present.[1]