HD 168607

HD 168607

HD 168607 is the right star of the pair below the Omega Nebula. The other is the hypergiant HD 168625.
Observation data
Epoch J2000      Equinox J2000
Constellation Sagittarius
Right ascension 18h 21m 14.889s
Declination −16° 22 31.76
Apparent magnitude (V) 8.12 - 8.29
Characteristics
Spectral type B9Ia+
U−B color index 0.41
B−V color index 1.54
J−K color index 1.06
Variable type LBV
Astrometry
Radial velocity (Rv)−30 km/s
Proper motion (μ) RA: 0.563 mas/yr
Dec.: −1.468 mas/yr
Parallax (π)0.6438±0.0603 mas
Distance5,100 ± 500 ly
(1,600 ± 100 pc)
Absolute magnitude (MV)−8.4
Details
Radius187 R
Luminosity240,000 L
Surface gravity (log g)1.0 cgs
Temperature9,300 K
Other designations
V4029 Sgr, HD 168607, BD−16°4829, SAO 161374, HIP 89956, AAVSO 1815-16
Database references
SIMBADdata

HD 168607 (V4029 Sagittarii) is a blue hypergiant and luminous blue variable (LBV) star located in the constellation of Sagittarius, easy to see with amateur telescopes. It forms a pair with HD 168625, also a blue hypergiant and possible luminous blue variable, that can be seen at the south-east of M17, the Omega Nebula.