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27 Cancri
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Cancer
Right ascension 08h 26m 43.94035s [1]
Declination +12° 39′ 16.6066″ [1]
Apparent magnitude (V) +5.56 [2]
Characteristics
Evolutionary stage Asymptotic giant branch [3]
Spectral type M3 IIIa [4]
B−V color index 1.608±0.002 [2]
Variable type SRb [3]
Astrometry
Radial velocity (Rv)−8.30±0.31 [5] km/s
Proper motion (μ) RA: −19.760 [1]  mas/ yr
Dec.: −104.664 [1]  mas/ yr
Parallax (π)3.3094 ± 0.3176  mas [1]
Distance990 ± 90  ly
(300 ± 30  pc)
Absolute magnitude (MV)−1.62 [2]
Details
Radius119 [1]  R
Luminosity2,455+707
−550
[6]  L
Surface gravity (log g)1.00 [6]  cgs
Temperature3,574 [6]  K
Metallicity [Fe/H]0.00 [6]  dex
Other designations
27 Cnc, BP Cancri, BD+13°1912, FK5 2658, GC 11525, HD 71250, HIP 41400, HR 3319, SAO 97819 [7]
Database references
SIMBAD data

27 Cancri is a single [8] star in the zodiac constellation of Cancer, located around 990  light-years away from the Sun. [1] It is visible to the naked eye as a faint, red-hued star with a typical apparent visual magnitude of around +5.56. [2] The star is moving closer to the Earth with a heliocentric radial velocity of −8.3 km/s. [5] It is a member of the Arcturus stream, a group of stars with high proper motion and metal-poor properties thought to be the remnants of a small galaxy consumed by the Milky Way. [9]

This is an aging red giant with a stellar classification of M3 IIIa, [4] currently on the asymptotic giant branch. [3] It is classified as a semiregular variable star of type SRb and its brightness varies from magnitude +5.41 to +5.75 with a period of 40 days. [10] The star is radiating around 2,455 [6] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,574 K. [6]

References

  1. ^ a b c d e f g 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.
  2. ^ a b c d 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 c Lebzelter, T.; Hron, J. (December 2003), "Technetium and the third dredge up in AGB stars. I. Field stars", Astronomy and Astrophysics, 411 (3): 533–542, arXiv: astro-ph/0310018, Bibcode: 2003A&A...411..533L, doi: 10.1051/0004-6361:20031458, S2CID  18879265.
  4. ^ a b 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, S2CID  123149047.
  5. ^ a b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv: 1208.3048, Bibcode: 2012A&A...546A..61D, doi: 10.1051/0004-6361/201219219, S2CID  59451347, A61.
  6. ^ a b c d e f Maas, Z. G.; et al. (December 2016), "Chlorine Abundances in Cool Stars", The Astronomical Journal, 152 (6): 14, arXiv: 1609.01626, Bibcode: 2016AJ....152..196M, doi: 10.3847/0004-6256/152/6/196, S2CID  118722950, 196.
  7. ^ "27 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-02-26.
  8. ^ Eggleton, P. P.; Tokovinin, A. A. (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.
  9. ^ Eggen, Olin (1971), "The Arcturus Group", Publications of the Astronomical Society of the Pacific, 83 (493): 271–85, Bibcode: 1971PASP...83..271E, doi: 10.1086/129120.
  10. ^ Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode: 2017ARep...61...80S, doi: 10.1134/S1063772917010085, S2CID  125853869.