A visual band light curve for V905 Scorpii. The red points are from Sterken et al. (1997), [1] and the blue points are ASAS data. [2] | |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Scorpius |
Right ascension | 17h 41m 59.025s [3] |
Declination | −33° 30′ 13.71″ [3] |
Apparent magnitude (V) | 6.66 [4] (6.3–6.9 [5]) |
Characteristics | |
Spectral type | LBV |
U−B color index | +0.30 [4] |
B−V color index | +1.21 [4] |
Variable type | LBV [5] |
Astrometry | |
Radial velocity (Rv) | −35 [6] km/s |
Proper motion (μ) |
RA: −1.75
[3]
mas/
yr Dec.: −1.49 [3] mas/ yr |
Parallax (π) | 0.54 ± 0.54 mas [3] |
Distance | 2,500 [7] pc |
Absolute magnitude (MV) | −8.9 [8] |
Details | |
Mass | 13 [8] M☉ |
Radius | 150–330 [5] R☉ |
Luminosity | 290,000 [7] L☉ |
Surface gravity (log g) | 0.55 [8] cgs |
Temperature | 8,000–12,000 [5] K |
Rotational velocity (v sin i) | 45 [5] km/s |
Other designations | |
Database references | |
SIMBAD | data |
HD 160529 (V905 Scorpii) is a luminous blue variable (LBV) star located in the constellation of Scorpius. With an apparent magnitude of around +6.8 cannot be seen with the naked eye except under very favourable conditions, but it is easy to see with binoculars or amateur telescopes.
V905 Sco has a peculiar variable spectral type with emission lines and P Cygni profiles. At visual maximum it is similar to an A9 star and at minimum close to B8. [5] The distance has been estimated at 2.5 kilo parsecs (8,200 light years) based on the assumption of an absolute magnitude of −8.9. [8] However this distance is uncertain and values between 1.9 kiloparsecs and 3.5 kiloparsecs have been proposed. [5]
Working with a distance of 2.5 kiloparsecs, the radius varies from 150 R☉ when quiescent to 330 R☉ in outburst. The temperature also varies, from 8,000K in outburst to 12,000K when quiescent. With these parameters, the apparent visual magnitude varies by 0.5 and the bolometric luminosity is constant at 180,000 L☉. [5]
Estimates of the surface gravity lead to a mass of 13 M☉ and a probable initial mass of 25 M☉ This suggests that V905 Sco is a former red supergiant star. [8]
A visual band light curve for V905 Scorpii. The red points are from Sterken et al. (1997), [1] and the blue points are ASAS data. [2] | |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Scorpius |
Right ascension | 17h 41m 59.025s [3] |
Declination | −33° 30′ 13.71″ [3] |
Apparent magnitude (V) | 6.66 [4] (6.3–6.9 [5]) |
Characteristics | |
Spectral type | LBV |
U−B color index | +0.30 [4] |
B−V color index | +1.21 [4] |
Variable type | LBV [5] |
Astrometry | |
Radial velocity (Rv) | −35 [6] km/s |
Proper motion (μ) |
RA: −1.75
[3]
mas/
yr Dec.: −1.49 [3] mas/ yr |
Parallax (π) | 0.54 ± 0.54 mas [3] |
Distance | 2,500 [7] pc |
Absolute magnitude (MV) | −8.9 [8] |
Details | |
Mass | 13 [8] M☉ |
Radius | 150–330 [5] R☉ |
Luminosity | 290,000 [7] L☉ |
Surface gravity (log g) | 0.55 [8] cgs |
Temperature | 8,000–12,000 [5] K |
Rotational velocity (v sin i) | 45 [5] km/s |
Other designations | |
Database references | |
SIMBAD | data |
HD 160529 (V905 Scorpii) is a luminous blue variable (LBV) star located in the constellation of Scorpius. With an apparent magnitude of around +6.8 cannot be seen with the naked eye except under very favourable conditions, but it is easy to see with binoculars or amateur telescopes.
V905 Sco has a peculiar variable spectral type with emission lines and P Cygni profiles. At visual maximum it is similar to an A9 star and at minimum close to B8. [5] The distance has been estimated at 2.5 kilo parsecs (8,200 light years) based on the assumption of an absolute magnitude of −8.9. [8] However this distance is uncertain and values between 1.9 kiloparsecs and 3.5 kiloparsecs have been proposed. [5]
Working with a distance of 2.5 kiloparsecs, the radius varies from 150 R☉ when quiescent to 330 R☉ in outburst. The temperature also varies, from 8,000K in outburst to 12,000K when quiescent. With these parameters, the apparent visual magnitude varies by 0.5 and the bolometric luminosity is constant at 180,000 L☉. [5]
Estimates of the surface gravity lead to a mass of 13 M☉ and a probable initial mass of 25 M☉ This suggests that V905 Sco is a former red supergiant star. [8]