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25 Cancri
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]
Distance148.4 ± 0.2  ly
(45.50 ± 0.07  pc)
Absolute magnitude (MV)2.85 [2]
Details
25 Cnc A
Mass1.51 [4]  M
Radius2.0 [1]  R
Luminosity6.60 [2]  L
Surface gravity (log g)4.01 [5]  cgs
Temperature6,487 [5]  K
Metallicity [Fe/H]−0.10 [5]  dex
Rotational velocity (v sin i)37.74±0.55 [6] km/s
Age2.50 [5]  Gyr
25 Cnc B
Mass0.34 [4]  M
Other designations
d2 Cnc, 25 Cnc, BD+17°1842, HD 71030, HIP 41319, HR 3299, SAO 97806, WDS 08258+1703 [7] [8]
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. ^ 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.
  2. ^ 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.
  3. ^ 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.
  4. ^ 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.
  5. ^ 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.
  6. ^ 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.
  7. ^ "25 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-02-25.
  8. ^ 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.
  9. ^ 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.
  10. ^ 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.