Astronomy and Space

Alpha Librae

Alpha Librae (α Librae, abbreviated Alpha Lib, α Lib) is a quadruple star system and, despite its 'alpha' designation, it is the second-brightest star in the constellation of Libra. The two components are designated α1 Librae and α2 Librae. The system bore the traditional name of Zubenelgenubi , though the International Astronomical Union now regards that name as only applying to α2 Librae. Alpha2 Librae is 0.33 degrees north of the ecliptic so it can be occulted by the Moon and (very rarely) by planets. It was occulted by Venus on October 25, 1947; the next occultation by a planet will be by Mercury on 10 November 2052. Both components are eclipsed (occulted) by the sun from about 7–9 November. Thus the star can be viewed the whole night, crossing the sky, in early May.

Also on this shelf

See also

• ▸Inertial Upper Stage
• ▸Apparent magnitude
• ▸John Zarnecki

Uncatalogued shelf

Text from Wikipedia; plate via Wikimedia Commons. Text CC BY-SA 4.0; plate freely licensed (see Commons). Source record. Images and catalogue data are reproduced from open-access collections.