1 Cancri

1 Cancri
Observation data; Epoch J2000.0 Equinox J2000.0
Constellation	Cancer
Right ascension	07h 56m 59.45262s
Declination	+15° 47′ 25.0019″
Apparent magnitude (V)	5.97
Characteristics
Spectral type	K3− III
B−V color index	1.285±0.007
Astrometry
Radial velocity (Rv)	+13.55±0.12 km/s
Proper motion (μ)	RA: −26.731 mas/yr ; Dec.: −42.7591 mas/yr
Parallax (π)	6.9810 ± 0.0694 mas
Distance	467 ± 5 ly ; (143 ± 1 pc)
Absolute magnitude (MV)	0.03
Details
Mass	1.1 M☉
Radius	18.7 R☉
Luminosity	199 L☉
Surface gravity (log g)	2.03 cgs
Temperature	4,231 K
Metallicity [Fe/H]	−0.01 dex
Other designations
	1 Cnc, BD+16°1590, FK5 1208, HD 64960, HIP 38848, HR 3095, SAO 97399
Database references
SIMBAD	data

1 Cancri is a single^[2] star in the zodiac constellation of Cancer, positioned near the border with Gemini at a distance of around 467 light years from the Sun. It is barely visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.97. The object is moving further from the Earth with a heliocentric radial velocity of +14 km/s.

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,^[9] which, at its estimated distance, equates to a physical radius of about 19 times the radius of the Sun. It is radiating 199 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,231 K.

References

^ ^a ^b ^c ^d ^e ^f ^g 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 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 ^c 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.
^ ^a ^b 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.
^ Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A.; Matijevič, G.; Monari, G.; Cantat-Gaudin, T.; Weiler, M.; Khan, S.; Miglio, A.; Carrillo, I.; Romero-Gómez, M.; Minchev, I.; de Jong, R. S.; Antoja, T.; Ramos, P.; Steinmetz, M.; Enke, H. (August 2019), "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18", Astronomy & Astrophysics, 628: A94, arXiv:1904.11302, Bibcode:2019A&A...628A..94A, doi:10.1051/0004-6361/201935765, ISSN 0004-6361.
^ Stassun, Keivan G.; et al. (September 2018), "The TESS Input Catalog and Candidate Target List", The Astronomical Journal, 156 (3): 102, arXiv:1706.00495, Bibcode:2018AJ....156..102S, doi:10.3847/1538-3881/aad050, ISSN 0004-6256.
^ ^a ^b ^c Sprague, Dani; et al. (8 March 2022), "APOGEE Net: An Expanded Spectral Model of Both Low-mass and High-mass Stars", The Astronomical Journal, 163 (4): 152, arXiv:2201.03661, Bibcode:2022AJ....163..152S, doi:10.3847/1538-3881/ac4de7, eISSN 1538-3881, ISSN 0004-6256.
^ "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