Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Sagittarius |
Right ascension | 18h 15m 12.90641s [1] |
Declination | −20° 43′ 41.7738″ [1] |
Apparent magnitude (V) | 5.37 [2] |
Characteristics | |
Spectral type | O9.7 Iab [3] or B0 Iab [4] |
B−V color index | 0.007±0.004 [5] |
Astrometry | |
Radial velocity (Rv) | −6.3±2.8 [6] km/s |
Proper motion (μ) |
RA: +1.60
[1]
mas/
yr Dec.: −1.51 [1] mas/ yr |
Parallax (π) | 0.10 ± 0.45 mas [1] |
Distance | 4,200±650
[7]
ly (1,300±200 pc) |
Details [8] | |
15 Sgr Aa | |
Mass | ~30 [4] M☉ |
Radius | 28.6±12.5 R☉ |
Luminosity | 4.47+3.85 −2.07×105 L☉ |
Surface gravity (log g) | 3.10 cgs |
Temperature | 28,000±1,000 K |
Rotational velocity (v sin i) | 83±7 [4] km/s |
Other designations | |
Database references | |
SIMBAD | data |
15 Sagittarii is a blue-hued binary star [10] system in the southern zodiac constellation of Sagittarius. The estimated distance based upon photometry is around 4,200 ly (1,300 pc). [7] It is faintly visible to the naked eye with an apparent visual magnitude of 5.37. [2] The system is moving closer to the Sun with a heliocentric radial velocity of around −6 km/s. [6]
Chini et al. (2012) identify this as a double-lined spectroscopic binary star system. [10] It shows a stellar classification of O9.7 Iab, [3] matching a massive O-type supergiant star. Along with the O-type star 16 Sgr (HD 167263), it is ionizing an H II region along the western edge of the molecular cloud L291. [11]
The Washington Double Star Catalog lists four companions within a 2 arcsecond angular radius. [12]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Sagittarius |
Right ascension | 18h 15m 12.90641s [1] |
Declination | −20° 43′ 41.7738″ [1] |
Apparent magnitude (V) | 5.37 [2] |
Characteristics | |
Spectral type | O9.7 Iab [3] or B0 Iab [4] |
B−V color index | 0.007±0.004 [5] |
Astrometry | |
Radial velocity (Rv) | −6.3±2.8 [6] km/s |
Proper motion (μ) |
RA: +1.60
[1]
mas/
yr Dec.: −1.51 [1] mas/ yr |
Parallax (π) | 0.10 ± 0.45 mas [1] |
Distance | 4,200±650
[7]
ly (1,300±200 pc) |
Details [8] | |
15 Sgr Aa | |
Mass | ~30 [4] M☉ |
Radius | 28.6±12.5 R☉ |
Luminosity | 4.47+3.85 −2.07×105 L☉ |
Surface gravity (log g) | 3.10 cgs |
Temperature | 28,000±1,000 K |
Rotational velocity (v sin i) | 83±7 [4] km/s |
Other designations | |
Database references | |
SIMBAD | data |
15 Sagittarii is a blue-hued binary star [10] system in the southern zodiac constellation of Sagittarius. The estimated distance based upon photometry is around 4,200 ly (1,300 pc). [7] It is faintly visible to the naked eye with an apparent visual magnitude of 5.37. [2] The system is moving closer to the Sun with a heliocentric radial velocity of around −6 km/s. [6]
Chini et al. (2012) identify this as a double-lined spectroscopic binary star system. [10] It shows a stellar classification of O9.7 Iab, [3] matching a massive O-type supergiant star. Along with the O-type star 16 Sgr (HD 167263), it is ionizing an H II region along the western edge of the molecular cloud L291. [11]
The Washington Double Star Catalog lists four companions within a 2 arcsecond angular radius. [12]