82 Cancri is a solitary,[3] 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,[2] it is dimly visible to the naked eye on a dark night. This star is located at a distance of approximately 540 light years from the Sun based on parallax. 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 km/s.[4]
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Cancer |
| Right ascension | 09h 15m 13.85196s[1] |
| Declination | +14° 56′ 29.4401″[1] |
| Apparent magnitude (V) | +5.33[2] |
| Characteristics | |
| Spectral type | K1 III[3] |
| U−B color index | +1.31[2] |
| B−V color index | +1.32[2] |
| Astrometry | |
| Radial velocity (Rv) | +27.49±0.19[4] km/s |
| Proper motion (μ) | RA: −40.874[1] mas/yr Dec.: −11.835[1] mas/yr |
| Parallax (π) | 6.0793 ± 0.1222 mas[1] |
| Distance | 540 ± 10 ly (164 ± 3 pc) |
| Absolute magnitude (MV) | −0.98[5] |
| Details | |
| Mass | 2.56±0.13[6] M☉ |
| Radius | 31.01+1.09 −3.52[1] R☉ |
| Luminosity | 307.4±7.3[1] L☉ |
| Temperature | 4,340+270 −74[1] K |
| Metallicity [Fe/H] | −0.195±0.099[7] dex |
| Rotational velocity (v sin i) | 1.3±1.0[8] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved K-type giant star with a stellar classification of K1 III,[3] having exhausted the supply of hydrogen at its core then cooled and expanded off the main sequence. The star currently has 31[1] times the girth of the Sun and is spinning slowly with a projected rotational velocity. It is radiating over 300 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,340 K.[1] Based on its abundance of iron, the star has a lower abundances of heavier elements than the Sun.[7]
References
edit- ^ a b c d e f g h i j 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.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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.
- ^ 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
- ^ 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.
- ^ 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.
- ^ "pi.02 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-14.
- ^ 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.
- ^ 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.