44 Andromedae
44 Andromedae is a single,[7] yellow-white hued star in the northern constellation of Andromeda.[6] 44 Andromedae is the Flamsteed designation. It has an apparent visual magnitude of approximately 5.67,[2] which indicates it is a dim star that is just visible to the naked eye on a dark night. The annual parallax shift as measured by the Hipparcos spacecraft is 18.8145 mas,[1] which yields a distance estimate of around 173 light years. It is moving closer to the Sun with a radial velocity of −14 km/s.[4]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 01h 10m 18.74041s[1] |
| Declination | +42° 04′ 53.3100″[1] |
| Apparent magnitude (V) | 5.67[2] |
| Characteristics | |
| Spectral type | F8 V[3] |
| U−B color index | +0.12[2] |
| B−V color index | +0.59[2] |
| Astrometry | |
| Radial velocity (Rv) | −14.2±0.2[4] km/s |
| Proper motion (μ) | RA: −135.569(38)[1] mas/yr Dec.: −41.790(30)[1] mas/yr |
| Parallax (π) | 18.8145 ± 0.0376 mas[1] |
| Distance | 173.4 ± 0.3 ly (53.2 ± 0.1 pc) |
| Absolute magnitude (MV) | +2.07[5] |
| Details[3] | |
| Mass | 1.64 M☉ |
| Radius | 3.58±0.19 R☉ |
| Luminosity | 12.9 L☉ |
| Surface gravity (log g) | 3.78±0.07 cgs |
| Temperature | 6,028±32 K |
| Metallicity [Fe/H] | −0.01±0.04 dex |
| Rotation | 15.2 d |
| Rotational velocity (v sin i) | 11.6±0.8 km/s |
| Age | 2.59 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This star has been assigned a stellar classification of F8 V,[3] which indicates it is an ordinary F-type main-sequence star. However, Gray et al. (2001) gave it a class of F9 IV, suggesting it is instead a subgiant star that is evolving away from the main sequence as the hydrogen fuel at its core becomes exhausted.[8] It is an estimated 2.6 billion years old and is rotating with a period of 15.2 days. The star has 1.64 times the mass of the Sun and 3.6 times the Sun's radius. It is radiating 13 times the Sun's luminosity from its photosphere at an effective temperature of 6,028 K.[3] It appears overluminous for a star of its type which may indicate the presence of a bright companion, but no radial velocity variation has been detected.[9]
References
- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ a b c d Guetter, H. H.; Hewitt, A. V. (June 1984), "Photoelectric UBV photometry for 317 PZT and VZT stars", Publications of the Astronomical Society of the Pacific, 96: 441–443, Bibcode:1984PASP...96..441G, doi:10.1086/131362.
- ^ a b c d Marsden, S. C.; et al. (November 2014), "A BCool magnetic snapshot survey of solar-type stars", Monthly Notices of the Royal Astronomical Society, 444 (4): 3517–3536, arXiv:1311.3374, Bibcode:2014MNRAS.444.3517M, doi:10.1093/mnras/stu1663, S2CID 53988884.
- ^ a b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- ^ HD 6920, database entry, The Geneva-Copenhagen Survey of Solar neighbourhood, J. Holmberg et al., 2007, CDS ID V/117A. Accessed on line November 19, 2008.
- ^ a b "44 And". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-12-28.
- ^ 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.
- ^ Gray, R. O.; Napier, M. G.; Winkler, L. I. (April 2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars", The Astronomical Journal, 121 (4): 2148–2158, Bibcode:2001AJ....121.2148G, doi:10.1086/319956.
- ^ Griffin, R. F.; Suchkov, A. A. (July 2003), "The Nature of Overluminous F Stars Observed in a Radial-Velocity Survey", The Astrophysical Journal Supplement Series, 147 (1): 103–144, Bibcode:2003ApJS..147..103G, doi:10.1086/367855.