HD 180262
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquila[1] |
| Right ascension | 19h 15m 20.08999s[2] |
| Declination | +15° 05′ 01.1456″[2] |
| Apparent magnitude (V) | 5.75[3] |
| Characteristics | |
| Spectral type | G8II-III[3] |
| U−B color index | +0.85[4] |
| B−V color index | +1.067±0.015[1] |
| R−I color index | 0.54 |
| Astrometry | |
| Radial velocity (Rv) | −25.2[5] km/s |
| Proper motion (μ) | RA: +1.178 mas/yr[2] Dec.: −10.948 mas/yr[2] |
| Parallax (π) | 5.392±0.0624 mas[2] |
| Distance | 605 ± 7 ly (185 ± 2 pc) |
| Absolute magnitude (MV) | −1.04[1] |
| Details | |
| Mass | 4.10+0.04 −0.20[2] M☉ |
| Radius | 23.59+0.56 −0.51[2] R☉ |
| Luminosity | 257.7+6.6 −4.5[2] L☉ |
| Surface gravity (log g) | 2.245±0.001[2] cgs |
| Temperature | 4,910+2 −3[2] K |
| Metallicity [Fe/H] | 0.21[6] dex |
| Rotational velocity (v sin i) | 1.4[7] km/s |
| Other designations | |
| BD+14°3846, HD 180262, HIP 94624, HR 7300, SAO 104655, WDS J19153+1505A[8] | |
| Database references | |
| SIMBAD | data |
HD 180262 is one member of a wide double star in the equatorial constellation of Aquila. The pair have a combined apparent visual magnitude of 5.57,[4] which is bright enough to be dimly visible to the naked eye. Based on a parallax shift of 5.392 mas, it is located at a distance of 605 light-years (185 pc). It is drifting closer with a line of sight velocity component of −25 km/s.[5]
The pair have an angular separation of 89.823 arc second as of 2008.[3] The dual nature was discovered by Otto Struve and reported in 1875.[9] HD 180262 has a visual magnitude of 5.75[3] and a stellar classification of G8II-III.[3] It is presenting as an evolved giant star that has exhausted the supply of hydrogen at its core. With four times the mass of the Sun, the star has expanded to 24 times the Sun's radius. It is radiating 257 times the luminosity of the Sun from its photosphere at an effective temperature of 4,910 K.[2]
The secondary is HD 180243, an ordinary A-type main-sequence star with a class of A1V.[3] It is two magnitudes fainter than HD 180262, with a visual magnitude of 7.69.[3]
References
[edit]- ^ a b c 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 XHIP record for this object at VizieR.
- ^ a b c d e f g h i j Vallenari, A.; et al. (Gaia collaboration) (2023), "Gaia Data Release 3. Summary of the content and survey properties", Astronomy and Astrophysics, 674: A1, arXiv:2208.00211, Bibcode:2023A&A...674A...1G, doi:10.1051/0004-6361/202243940, S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e f g 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
- ^ a b Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data. SIMBAD, Bibcode:1986EgUBV........0M
- ^ a b Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
- ^ Greenstein, Jesse L.; Keenan, Philip C. (January 1958), "Abundances of Metals, CN, and CH in Giant Stars", Astrophysical Journal, 127: 172, Bibcode:1958ApJ...127..172G, doi:10.1086/146449
- ^ Lèbre, A.; de Laverny, P.; Do Nascimento, J. D. Jr.; de Medeiros, J. R. (May 2006), "Lithium abundances and rotational behavior for bright giant stars", Astronomy and Astrophysics, 450 (3): 1173–1179, Bibcode:2006A&A...450.1173L, doi:10.1051/0004-6361:20053485
- ^ "HD 180262", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2026-04-08.
- ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466, Bibcode:2001AJ....122.3466M, doi:10.1086/323920, retrieved 2015-07-22.
