 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[1] |
| Declination | −16° 22′ 31.76″[1] |
| Apparent magnitude (V) | 8.12 - 8.29[2] |
| Characteristics | |
| Spectral type | B9Ia+[3] |
| U−B color index | 0.41[4] |
| B−V color index | 1.54[4] |
| J−K color index | 1.06[4] |
| Variable type | LBV[5] |
| Astrometry | |
| Radial velocity (Rv) | −30[6] km/s |
| Proper motion (μ) | RA: 0.563 mas/yr Dec.: −1.468[7] mas/yr |
| Parallax (π) | 0.6438 ± 0.0603 mas[7] |
| Distance | 5,100 ± 500 ly (1,600 ± 100 pc) |
| Absolute magnitude (MV) | −8.4[8] |
| Details | |
| Radius | 187[8] R☉ |
| Luminosity | 240,000[8] L☉ |
| Surface gravity (log g) | 1.0[8] cgs |
| Temperature | 9,300[8] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
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.
- ^ a b Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
- ^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1: B/gcvs. Bibcode:2009yCat....102025S.
- ^ Chentsov, E. L.; Ermakov, S. V.; Klochkova, V. G.; Panchuk, V. E.; Bjorkman, K. S.; Miroshnichenko, A. S. (2003). "An atlas of spectra of B6-A2 hypergiants and supergiants from 4800 to 6700Å" (PDF). Astronomy and Astrophysics. 397 (3): 1035–1042. Bibcode:2003A&A...397.1035C. doi:10.1051/0004-6361:20021430.
- ^ a b c Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237: 0. Bibcode:2002yCat.2237....0D.
- ^ Nazé, Y.; Rauw, G.; Hutsemékers, D. (2012). "The first X-ray survey of Galactic luminous blue variables". Astronomy & Astrophysics. 538: A47. arXiv:1111.6375. Bibcode:2012A&A...538A..47N. doi:10.1051/0004-6361/201118040. S2CID 43688343.
- ^ Kharchenko, N. V.; Scholz, R.-D.; Piskunov, A. E.; Röser, S.; Schilbach, E. (2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ˜55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten. 328 (9): 889. arXiv:0705.0878. Bibcode:2007AN....328..889K. doi:10.1002/asna.200710776. S2CID 119323941.
- ^ a b Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e Van Genderen, A. M.; Van Den Bosch, F. C.; Dessing, F.; Fehmers, G. C.; Van Grunsven, J.; Van Der Heiden, R.; Janssens, A. M.; Kalter, R.; Van Der Meer, R. L. J.; Van Ojik, R.; Smit, J. M.; Zijderveld, M. J. (1992). "Light variations of massive stars (Alpha Cygni variables). XIII - the B-type hypergiants R81 (LBV), HD 80077 (LBV?), HD 168607 = V 4029 Sagittarii (LBV) and HD 168625 = V 4030 Sagittarii". Astronomy and Astrophysics. 264: 88. Bibcode:1992A&A...264...88V.