Upsilon Librae has the stellar classification of K3III, which makes the star an orange giant. It is a multiple star system with an apparent magnitude of 3.60. It is approximately 195 light years distant from the Sun.
Alpha Librae is the second brightest star in Libra. It is a multiple star system whose two brightest components form a binary star and share a common proper motion through space. They are suspected members of the Castor Moving Group of stars, which share a common origin about 200 million years ago.
The Alpha Librae system lies close to the ecliptic and can be occulted by the Moon and, much less frequently, by planets. It will next be occulted by a planet (Mercury) on November 10, 2052.
The name Zubenelgenubi is derived from the Arabic phrase al-zuban al-janūbiyy, which means “the southern claw.” The system is also sometimes known as Kiffa Australis or Elkhiffa Australis. Both names are partial Latin translations and come from the Arabic phrase al-kiffah al-janūbiyy, which means “the southern pan (of the scales).” An older Latin name for the star is Lanx Australis, or “the southern scale.”
Beta Librae is the brightest star in the constellation. It has an apparent magnitude of 2.61 and is approximately 185 light years distant from the solar system.
It has the stellar classification of B8 V, which means that it is a blue-white dwarf. Beta Librae is a very fast spinner, with a projected rotational velocity of 250 km/s. It has 4.9 times the solar radius and is approximately 130 times more luminous than the Sun.
The star’s proper name, Zubeneschamali, comes from the Arabic phrase al-zuban al-šamāliyya, which means “the northern claw.” The star’s Latin name is Lanx Borealis, or “the northern scale.”
Tau Librae is a blue-white dwarf with the stellar classification of B2.5V. It has an apparent magnitude of 3.66 and is approximately 445 light years distant. The star has 3.2 times the Sun’s radius.
Sigma Librae is a red giant star with the stellar classification of M3/M4 III. It has an apparent magnitude of 3.29 and is approximately 288 light years distant from the Sun. The star’s traditional name, Brachium, means “arm” in Latin. It is also sometimes known as Cornu (Latin for “horn”) and Zubenalgubi (“southern claw” in Arabic).
Sigma Librae used to have the Bayer designation Gamma Scorpii even though it lies quite far from the border with Scorpius constellation. It only became Sigma Librae in the 19th century, and the designation was confirmed by the International Astronomical Union on July 31, 1930.
Brachium is a semi-regular variable star with a single pulsation period of 20 days. It exhibits small variations in magnitude of 0.10 to 0.15 over short periods of 15 to 20 minutes every 2.5 to 3 hours or so.
Gamma Librae is an orange giant belonging to the stellar class K0 III. It has an apparent magnitude of 3.91 and is approximately 152 light years distant from the solar system. It has 2.15 solar masses and is about 71 times more luminous than the Sun.
The star’s traditional name, Zubenelakrab, or Zuben-al-Akrab, is derived from the Arabic phrase al-Zuban al-Aqrab, which means “the shears of the scorpion.”
Theta Librae is an orange giant with the stellar classification of K0 III. It has a visual magnitude of 4.136 and is approximately 163 light years distant from Earth. It has a mass about 84 percent greater than the Sun’s and it is approximately 35 times more luminous.
Delta Librae belongs to the spectral class B9.5V. It is a blue-white main sequence star with an apparent magnitude of 4.43, approximately 300 light years from Earth. It is classified as an eclipsing variable star. It has a period of 2.3272 days and its luminosity varies from 4.43 to 5.81 magnitudes.
The star’s traditional name, Zuben Elakribi, or Zuben-el-Akribi, comes from the Arabic az-zubānā al-ʿaqrab, which means “the claws of the scorpion.”