Astronomy:HD 39225
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Auriga |
| Right ascension | 05h 52m 40.09222s[1] |
| Declination | +33° 55′ 02.8721″[1] |
| Apparent magnitude (V) | 6.04[2] (5.82–6.07)[3] |
| Characteristics | |
| Evolutionary stage | AGB[4] |
| Spectral type | M1+III Fe-1[5] |
| U−B color index | 1.97 |
| B−V color index | 1.579±0.021 |
| Variable type | suspected[3] |
| Astrometry | |
| Radial velocity (Rv) | 98.35±0.53[1] km/s |
| Proper motion (μ) | RA: 18.569[1] mas/yr Dec.: 8.812[1] mas/yr |
| Parallax (π) | 5.2412 ± 0.1841[1] mas |
| Distance | 620 ± 20 ly (191 ± 7 pc) |
| Absolute magnitude (MV) | −0.77[2] |
| Details | |
| Radius | 43.0±3.5[1] R☉ |
| Luminosity | 398.6±16.2[1] L☉ |
| Temperature | 3,934±51[6] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 39225, also known as HR 2028, is a variable star in the northern constellation Auriga, located around 620 light years away from the Sun. It is visible to the naked eye as a faint, red-hued star with an apparent visual magnitude of around 6.04.[2] This is a suspected runaway star[8] that is moving away from the Sun with a heliocentric radial velocity of 98 km/s.[1]
Currently on the asymptotic giant branch,[4] this is an evolved red giant star with a stellar classification of M1+III Fe-1.[5] The suffix notation indicates an underabundance of iron in the stellar atmosphere compared to similar stars of its class. It is suspected of varying in brightness between magnitudes 5.82 and 6.07.[3] Having exhausted the hydrogen at its core, it has expanded to around 43 times the Sun's radius.[1] It shines with a luminosity approximately 398.6[1] times that of the Sun and has a surface temperature of 3,934 K.[6]
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.
- ↑ 3.0 3.1 3.2 Watson, Christopher (18 January 2010). "NSV 2681". The International Variable Star Index. American Association of Variable Star Observers. http://www.aavso.org/vsx/index.php?view=detail.top&oid=41305.
- ↑ 4.0 4.1 Eggen, Olin J. (1992). "Asymptotic giant branch stars near the sun". The Astronomical Journal 104: 275. doi:10.1086/116239. Bibcode: 1992AJ....104..275E.
- ↑ 5.0 5.1 Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series 71: 245. doi:10.1086/191373. Bibcode: 1989ApJS...71..245K.
- ↑ 6.0 6.1 van Belle, G. T. et al. (2009). "Supergiant temperatures and linear radii from near-infrared interferometry". Monthly Notices of the Royal Astronomical Society 394 (4): 1925. doi:10.1111/j.1365-2966.2008.14146.x. Bibcode: 2009MNRAS.394.1925V.
- ↑ "HD 39225". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+39225.
- ↑ Tetzlaff, N. et al. (January 2011). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society 410 (1): 190–200. doi:10.1111/j.1365-2966.2010.17434.x. Bibcode: 2011MNRAS.410..190T.
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