HD 180450
HD 180450 is a single[4] star in the northern constellation of Lyra, positioned about half a degree to the NNW of the globular cluster M56.[5] At an apparent visual magnitude of 5.88,[2] it is dimly visible to the naked eye under good viewing conditions. This star is located at a distance of approximately 1,400 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −64.4 km/s.[1]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Lyra |
| Right ascension | 19h 15m 24.85937s[1] |
| Declination | +30° 31′ 34.9760″[1] |
| Apparent magnitude (V) | 5.88[2] |
| Characteristics | |
| Spectral type | M1IIIab[2] |
| U−B color index | +2.03 |
| B−V color index | +1.665±0.007[2] |
| Astrometry | |
| Radial velocity (Rv) | −64.43±0.23[1] km/s |
| Proper motion (μ) | RA: 34.425[1] mas/yr Dec.: −26.081[1] mas/yr |
| Parallax (π) | 2.37 ± 0.61 mas[1] |
| Distance | approx. 1,400 ly (approx. 400 pc) |
| Absolute magnitude (MV) | −2.03[2] |
| Details | |
| Radius | 68+12 −13[1] R☉ |
| Luminosity | 1,002±34[1] L☉ |
| Temperature | 3,947+433 −305[1] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an aging red giant star with a stellar classification of M1IIIab,[2] It is currently on the asymptotic giant branch,[6] having exhausted the supply of hydrogen in its core and evolved of the main sequence. It has expanded to ~68 times the radius of the Sun and is radiating a thousand times the Sun' luminosity from its enlarged photosphere at en effective temperature of 3,947 K.[1]
References
- 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.
- Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- "HD 180450". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-10-14.
- Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- Sinnott, Roger W.; Perryman, Michael A. C. (1997), Millennium Star Atlas, vol. 3, Sky Publishing Corporation and the European Space Agency, p. 1174, ISBN 0-933346-84-0.
- Eggen, Olin J. (July 1992), "Asymptotic giant branch stars near the sun", Astronomical Journal, 104 (1): 275–313, Bibcode:1992AJ....104..275E, doi:10.1086/116239.
