Astronomy:25 Cancri
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| 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[1] mas |
| 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 |
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]
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
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 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 Harlan, E. A. (September 1969), "MK classifications for F- and G-type stars. I", Astronomical Journal 74: 916–919, doi:10.1086/110881, Bibcode: 1969AJ.....74..916H.
- ↑ 4.0 4.1 4.2 4.3 4.4 Tokovinin, Andrei (2014), "From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs", The Astronomical Journal 147 (4): 87, doi:10.1088/0004-6256/147/4/87, Bibcode: 2014AJ....147...87T.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 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, doi:10.1051/0004-6361/201016276, Bibcode: 2011A&A...530A.138C.
- ↑ 6.0 6.1 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, doi:10.1093/mnras/stv1466, Bibcode: 2015MNRAS.453.3766L.
- ↑ "25 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=25+Cnc.
- ↑ 8.0 8.1 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, doi:10.1088/0004-637X/799/1/4, ISSN 0004-637X, Bibcode: 2015ApJ...799....4R.
- ↑ 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, doi:10.1086/427854, Bibcode: 2005AJ....129.1483L.
- ↑ Cowley, A. P. (April 1976), "Spectral classification of the bright F stars", Publications of the Astronomical Society of the Pacific 88: 95–110, doi:10.1086/129905, Bibcode: 1976PASP...88...95C.
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