Ara (constellation)
| Constellation | |
| Abbreviation | Ara |
|---|---|
| Genitive | Arae |
| Pronunciation | /ˈɛərə/, genitive /ˈɛəriː/ |
| Symbolism | the Altar |
| Right ascension | 16h 34m 16.9497s–18h 10m 41.3407s |
| Declination | −45.4859734°–−67.6905823° |
| Area | 237 sq. deg. (63rd) |
| Main stars | 8 |
| Bayer/Flamsteed stars | 17 |
| Stars brighter than 3.00m | 2 |
| Stars within 10.00 pc (32.62 ly) | 3 |
| Brightest star | β Ara (2.84m) |
| Nearest star | Gliese 674 |
| Messier objects | 0 |
| Meteor showers | 0 |
| Bordering constellations | |
| Visible at latitudes between +22° and −90°. Best visible at 21:00 (9 p.m.) during the month of July. | |
Ara (Latin for "the Altar") is a southern constellation between Scorpius, Telescopium, Triangulum Australe, and Norma. Under its Greek name Βωμός, Bōmǒs, it was one of the 48 classical constellations described by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations designated by the International Astronomical Union.
The orange supergiant Beta Arae is the brightest star in Ara, with a near-constant apparent magnitude of 2.85, and is marginally brighter than the blue-white Alpha Arae. Seven star systems are known to host planets. Sunlike Mu Arae hosts four known planets. Gliese 676 is a (gravity-paired) binary red dwarf system with four known planets.
The Milky Way crosses the northwestern part of Ara. Within the constellation is Westerlund 1, a super star cluster that contains the red supergiant Westerlund 1-26, one of the largest stars known.