A constellation of the zodiac, representing a pair of scales. The Sun lies in Libra for the first three weeks of November. Alpha Librae (Zubenelgenubi) is a wide double. Beta Librae (Zubeneschamali) is the constellation’s brightest star, magnitude 2.6. The two star names come from the Arabic meaning ’southern claw’ and ‘northern claw’, and arise because Libra once represented the claws of the scorpion, Scorpius, which it adjoins. Delta Librae is an Algol star, an eclipsing binary that varies between magnitudes 4.9 and 5.9 in a period of 2 days 8 hours.