Beta Centauri (β Cen, β Centauri) is a trinary star system in the southern constellation of Centaurus. The system's combined apparent visual magnitude of 0.61, makes it the second brightest star in the constellation Centaurus and the tenth brightest star in the night sky. It has the traditional names Hadar and Agena. The name Hadar comes from the Arabic حضار (the root's meaning is "to be present" or "on the ground" or "settled, civilized area"), while the name Agena may ultimately be derived from the Latin gena 'knees'. The Chinese name for the star is 马腹一 (Mandarin: mǎ fù yī, the First Star of the Horse's Abdomen).