25 Cancri is a common proper motion[4] star system in the zodiac constellation of Cancer, located around 148 light-years away from the Sun. It has the Bayer designation d2 Cancri (d2 Cnc); 25 Cancri (25 Cnc) is the Flamsteed designation. It is near the lower limit of visibility to the naked eye in good viewing conditions, appearing as a dim, yellow-white-hued star with a combined apparent visual magnitude of 6.11.[2] The pair have a relatively high proper motion, traversing the celestial sphere at an angular rate of 0.245″ per year.[9] It is moving further from the Earth with a heliocentric radial velocity of +38 km/s.[1]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cancer |
| Right ascension | 08h 25m 49.87726s[1] |
| Declination | +17° 02′ 46.5717″[1] |
| Apparent magnitude (V) | 6.11[2] |
| Characteristics | |
| Spectral type | F6 V[3] |
| B−V color index | 0.448±0.005[2] |
| Astrometry | |
| Radial velocity (Rv) | +37.56±0.13[1] km/s |
| Proper motion (μ) | RA: −191.567[1] mas/yr Dec.: −151.554[1] mas/yr |
| Parallax (π) | 21.9803 ± 0.0321 mas[1] |
| Distance | 148.4 ± 0.2 ly (45.50 ± 0.07 pc) |
| Absolute magnitude (MV) | 2.85[2] |
| Details | |
| 25 Cnc A | |
| Mass | 1.51[4] M☉ |
| Radius | 2.0[1] R☉ |
| Luminosity | 6.60[2] L☉ |
| Surface gravity (log g) | 4.01[5] cgs |
| Temperature | 6,487[5] K |
| Metallicity [Fe/H] | −0.10[5] dex |
| Rotational velocity (v sin i) | 37.74±0.55[6] km/s |
| Age | 2.50[5] Gyr |
| 25 Cnc B | |
| Mass | 0.34[4] M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
Based upon a stellar classification of F6 V,[3] the brighter component is an F-type main-sequence star that is generating energy through hydrogen fusion at its core. Cowley (1976) listed a class of F5 IIIm?,[10] which suggests it may be an Am star. However, this has not been confirmed.[6] It is about 2.5[5] billion years old with 1.51[4] times the mass of the Sun. The star is radiating 6.6[2] times the Sun's luminosity from its photosphere at an effective temperature of 6,487 K.[5]
The companion is 4.19 magnitudes fainter than the primary, and lies at an angular separation of 16.798″ along a position angle of 310°, as of 2013.[8] If the pair are gravitationally bound, then they orbit each other with a period of around 4.05 million years.[4]
References
edit- ^ a b c d e f g h 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 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.
- ^ a b Harlan, E. A. (September 1969), "MK classifications for F- and G-type stars. I", Astronomical Journal, 74: 916–919, Bibcode:1969AJ.....74..916H, doi:10.1086/110881.
- ^ a b c d e Tokovinin, Andrei (2014), "From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs", The Astronomical Journal, 147 (4): 87, arXiv:1401.6827, Bibcode:2014AJ....147...87T, doi:10.1088/0004-6256/147/4/87, S2CID 56066740.
- ^ a b c d e f Casagrande, L.; et al. (June 2011), "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s). Improved astrophysical parameters for the Geneva-Copenhagen Survey", Astronomy and Astrophysics, 530: A138, arXiv:1103.4651, Bibcode:2011A&A...530A.138C, doi:10.1051/0004-6361/201016276, S2CID 56118016.
- ^ a b LeBlanc, F.; et al. (November 2015), "Project VeSElkA: results of abundance analysis I - HD 71030, HD 95608, HD 116235 and HD 186568", Monthly Notices of the Royal Astronomical Society, 453 (4): 3766–3771, Bibcode:2015MNRAS.453.3766L, doi:10.1093/mnras/stv1466.
- ^ "25 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-02-25.
- ^ a b Riddle, Reed L.; et al. (January 1, 2015), "A Survey of the High Order Multiplicity of Nearby Solar-type Binary Stars with Robo-AO", The Astrophysical Journal, 799 (1): 4, arXiv:1411.0682, Bibcode:2015ApJ...799....4R, doi:10.1088/0004-637X/799/1/4, ISSN 0004-637X, S2CID 5642378.
- ^ Lépine, Sébastien; Shara, Michael M. (March 2005), "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)", The Astronomical Journal, 129 (3): 1483–1522, arXiv:astro-ph/0412070, Bibcode:2005AJ....129.1483L, doi:10.1086/427854, S2CID 2603568.
- ^ Cowley, A. P. (April 1976), "Spectral classification of the bright F stars", Publications of the Astronomical Society of the Pacific, 88: 95–110, Bibcode:1976PASP...88...95C, doi:10.1086/129905.