1 Cancri
1 Cancri is a single[2] star in the zodiac constellation of Cancer, positioned near the border with Gemini at a distance of around 470 light years from the Sun.[1] It is barely visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.97.[2] The object is moving further from the Earth with a heliocentric radial velocity of +14 km/s.[1]
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cancer |
Right ascension | 07h 56m 59.45230s[1] |
Declination | +15° 47′ 25.0026″[1] |
Apparent magnitude (V) | 5.97[2] |
Characteristics | |
Spectral type | K3− III[3] |
B−V color index | 1.285±0.007[4] |
Astrometry | |
Radial velocity (Rv) | +13.93±0.15[1] km/s |
Proper motion (μ) | RA: −26.794[1] mas/yr Dec.: −42.701[1] mas/yr |
Parallax (π) | 7.1899 ± 0.0958[1] mas |
Distance | 454 ± 6 ly (139 ± 2 pc) |
Absolute magnitude (MV) | 0.03[4] |
Details | |
Radius | 31[5] R☉ |
Luminosity | 137[1] L☉ |
Temperature | 4,367[1] K |
Other designations | |
Database references | |
SIMBAD | data |
This is an evolved giant star with a stellar classification of K3− III,[3] having exhausted the hydrogen at its core and expanded. It is specified as a spectral standard for that type.[3] The angular diameter of the star measured from a lunar occultation is 2.1±0.6 mas,[7] which, at its estimated distance, equates to a physical radius of about 31 times the radius of the Sun.[5] It is radiating 137[8] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,487 K.[8]
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.
- 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.
- Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
- 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.
- Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, 1 (3rd ed.), Birkhäuser, ISBN 978-3-540-29692-8. The radius (R*) is given by:
- "1 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-02-22.
- Richichi, A.; et al. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics, 431 (2): 773–777, Bibcode:2005A&A...431..773R, doi:10.1051/0004-6361:20042039
- McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x.