Tags: Star.
Gliese 581 (/ˈɡliːzə/ also known as HO Librae) is a main sequence red star with spectral type M3V located about 22 light years away from Earth in the constellation Libra. Its estimated mass is about a third of that of the Sun and it is the 89th closest known star to the Sun. Observations suggest that the star has a planetary system consisting of at least three likely four and controversially six planets. The existence of the planets Gliese 581 e b and c is certain.
