Omicron Sagittarii

ο Sagittarii

ο Sagittarii's position in Sagittarius (rendered in Celestia)
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Sagittarius
Right ascension	19^h 04^m 40.98^s [1]
Declination	−21° 44′ 29.4″ [1]
Apparent magnitude (V)	+3.76
Characteristics
Spectral type	K0III
Astrometry
Proper motion (μ)	RA: 76.35 ± 0.31 [1] mas/yr Dec.: −58.12 ± 0.18 [1] mas/yr
Parallax (π)	22.96 ± 0.24[1] mas
Distance	142 ± 1 ly (43.6 ± 0.5 pc)
Absolute magnitude (MV)	0.61
Other designations
Manubrij, ο Sagittarii, ο Sgr, Omicron Sgr, 39 Sagittarii, BD-21 5237, CCDM J19047-2144A, GC 26224, HD 177241, HIP 93683, HR 7217, IDS 18587-2153, PPM 269274, SAO 187643, ADS 11996, WDS J19047-2144A.

Omicron Sagittarii (Omicron Sgr, ο Sagittarii, ο Sgr) is a binary star in the constellation Sagittarius. ο Sagittarii is located 142 light years from Earth^[1] and is a spectral type K0 orange giant with an apparent magnitude of +3.77. It has a faint, 13th magnitude companion, ο Sagittarii B, 36 arc seconds away.

Because it is close to the ecliptic, ο Sagittarii can be occulted by the Moon and very rarely by planets. The last occultation of ο Sagittarii by a planet took place on 24 December 1937, when it was occulted by Mercury.

Name and etymology

• This star sometimes called by the name Manubrium of Manubrij, from Latin manus ‘hand’, the star does appear to mark the Archer's right ear.^[2]
• In Chinese, 建 (Jiàn), meaning Establishment, refers to an asterism consisting of ο Sagittarii ξ² Sagittarii, π Sagittarii, 43 Sagittarii, ρ¹ Sagittarii and υ Sagittarii. Consequently, ο Sagittarii itself is known as 建二 (Jiàn èr, English: the Second Star of Establishment.)^[3]

References

1. van Leeuwen, F. (2007). "HIP 93683". Hipparcos, the New Reduction. Retrieved 2009-12-04.
2. MANUBRIUM
3. (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 11 日