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82 Cancri

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82 Cancri
Location of 82 Cancri (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Cancer[1]
Right ascension 09h 15m 13.852s[2]
Declination +14° 56′ 29.43″[2]
Apparent magnitude (V) +5.33[3]
Characteristics
Spectral type K1 III[4]
U−B color index +1.31[3]
B−V color index +1.32[3]
Astrometry
Radial velocity (Rv)+27.49±0.19[5] km/s
Proper motion (μ) RA: −41.018 mas/yr[2]
Dec.: −11.304 mas/yr[2]
Parallax (π)5.6869±0.0902 mas[2]
Distance574 ± 9 ly
(176 ± 3 pc)
Absolute magnitude (MV)−0.98[1]
Details
Mass2.56±0.13[6] M
Radius31.32+0.85
−0.64
[2] R
Luminosity435+10
−12
[2] L
Surface gravity (log g)2.04±0.02[2] cgs
Temperature4,703+18
−27
[2] K
Metallicity [Fe/H]−0.195±0.099[7] dex
Rotational velocity (v sin i)1.3±1.0[8] km/s
Other designations
π2 Cnc, 82 Cancri, BD+15°2009, FK5 2733, HD 79554, HIP 45410, HR 3669, SAO 98456[9]
Database references
SIMBADdata

82 Cancri is a solitary,[4] orange-hued star in the zodiac constellation of Cancer. It has the Bayer designation Pi2 Cancri, which is Latinized from π2 Cancri; 82 Cancri is the star's Flamsteed designation. The star lies just a degree to the south of the ecliptic.[10] With an apparent visual magnitude of +5.33,[3] it is dimly visible to the naked eye on a dark night. This star is located at a distance of approximately 574 light-years (176 pc) from the Sun based on parallax measurements. At that range, the visual magnitude is diminished by an extinction of 0.10 magnitudes due to interstellar dust.[11] It is drifting further away with a radial velocity of +27.5 km/s.[5]

This is an evolved K-type giant star with a stellar classification of K1 III,[4] having exhausted the supply of hydrogen at its core then cooled and expanded off the main sequence. The star 2.6[6] times the Sun's mass and has expanded to 31[2] times the girth of the Sun. It is spinning slowly with a projected rotational velocity. This star is radiating 435 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,703 K.[2] Based on its abundance of iron, the star has a lower abundances of heavier elements than the Sun.[7]

References

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  1. ^ 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. XHIP record for this object at VizieR.
  2. ^ a b c d e f g h i j 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.
  3. ^ a b c d Rybka, E. (1969), "The corrected magnitudes and colours of 278 stars near S.A. 1-139 in the UBV system", Acta Astronomica, 19: 229, Bibcode:1969AcA....19..229R.
  4. ^ a b c 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.
  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 Kervella, Pierre; et al. (March 2019), "Stellar and substellar companions of nearby stars from Gaia DR2. Binarity from proper motion anomaly", Astronomy & Astrophysics, 623: 23, arXiv:1811.08902, Bibcode:2019A&A...623A..72K, doi:10.1051/0004-6361/201834371, S2CID 119491061, A72
  7. ^ a b Taylor, B. J. (February 1999), "Catalogs of temperatures and [Fe/H] averages for evolved G and K stars", Astronomy and Astrophysics Supplement, 134 (3): 523–524, Bibcode:1999A&AS..134..523T, doi:10.1051/aas:1999153.
  8. ^ De Medeiros, J. R.; et al. (2014), "A catalog of rotational and radial velocities for evolved stars", Astronomy and Astrophysics, 561, A126, arXiv:1312.3474, Bibcode:2014A&A...561A.126D, doi:10.1051/0004-6361/201220762, S2CID 54046583.
  9. ^ "pi.02 Cnc", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2017-06-14.
  10. ^ Sinnott, Roger W.; Perryman, Michael A. C. (1997), Millennium Star Atlas, vol. 2, Sky Publishing Corporation and the European Space Agency, p. 711, ISBN 0-933346-83-2.
  11. ^ Famaey, B.; et al. (January 2005), "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters", Astronomy and Astrophysics, 430 (1): 165–186, arXiv:astro-ph/0409579, Bibcode:2005A&A...430..165F, doi:10.1051/0004-6361:20041272, S2CID 17804304.