Gliese 581c is the light planet discovered (as 2007 Apr.) around a main sequence star (M3 star) using the radial velocity method. Gliese 581cSETI looked at Gliese 581 on two previous occasions as a potential candidate for extraterrestrial intelligence, but both examinations revealed no definitive proof.Like hot Venus ?The lower limit of the mass is only 5.03 times that of the earth. Its orbital semimajor axis is 0.073 AU, and completing its orbit around G1 581 every 13 days. It is the first small (~rocky) planet inside possible habitable zone.