42 Cancri

42 Cancri
Observation data
Epoch J2000      Equinox J2000
Constellation Cancer
Right ascension 08h 40m 43.20572s[1]
Declination +19° 43′ 09.5359″[1]
Apparent magnitude (V) 6.83[2]
Characteristics
Spectral type A7III[3]
B−V color index 0.202±0.004[2]
Astrometry
Radial velocity (Rv)+34.6±0.9[2] km/s
Proper motion (μ) RA: −36.167±0.102[1] mas/yr
Dec.: −12.105±0.063[1] mas/yr
Parallax (π)5.2981 ± 0.0548 mas[1]
Distance616 ± 6 ly
(189 ± 2 pc)
Absolute magnitude (MV)0.56[2]
Details
Mass2.39±0.03[4] M☉
Radius4.22±0.27[4] R☉
Luminosity51.5±0.7[1] L☉
Temperature7,607+258
−313[1] K
Metallicity [Fe/H]−0.08±0.03[4] dex
Rotational velocity (v sin i)195[5] km/s
Age603±28[4] Myr
Other designations
42 Cnc, BD+20° 2172, GC 11916, HD 73785, HIP 42578, SAO 98030, PPM 125583[6]
Database references
SIMBADdata

42 Cancri is a single[7] star in the northern zodiac constellation of Cancer. With an apparent visual magnitude of 6.83,[2] it is dimmer than what is considered the normal lower limit for visibility with the naked eye. The star is located at a distance of approximately 616 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +35 km/s.[2] 42 Cancri is a member of the Beehive Cluster (NGC 2632).[7]

The stellar classification of this star is A7III,[3] matching an A-type star that is in the giant stage. However, this may be a misclassification of a main sequence star.[8] It has also been classified as a spectroscopic binary,[5] although no orbital elements are published. 42 Cancri is an estimated 603[4] million years old and is spinning rapidly with a projected rotational velocity of 195 km/s.[5] The star has 2.39 times the mass of the Sun and 4.2 times the Sun's radius.[4] It is radiating 51.5[1] times the luminosity of the Sun from its photosphere at an effective temperature of 7,607 K.[1]

References

  1. ^ a b c d e f g h i 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 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 Gray, R. O.; et al. (2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars", The Astronomical Journal, 121 (4): 2148, Bibcode:2001AJ....121.2148G, doi:10.1086/319956, S2CID 117076031.
  4. ^ a b c d e f Bochanski, John J.; et al. (April 2018), "Fundamental Properties of Co-moving Stars Observed by Gaia", The Astronomical Journal, 155 (4): 17, arXiv:1801.00537, Bibcode:2018AJ....155..149B, doi:10.3847/1538-3881/aaaebe, S2CID 119256051, 149.
  5. ^ a b c Treanor, P. J. (1960), "Stellar rotation in galactic open clusters", Monthly Notices of the Royal Astronomical Society, 121 (6): 503, Bibcode:1960MNRAS.121..503T, doi:10.1093/mnras/121.6.503.
  6. ^ "42 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-08.
  7. ^ a b Mason, Brian D.; et al. (August 1993), "ICCD Speckle Observations of Binary Stars. IX. A Duplicity Survey of the Pleiades, Praesepe, and IC 4665 Clusters", Astronomical Journal, 106: 637, Bibcode:1993AJ....106..637M, doi:10.1086/116669.
  8. ^ Clampitt, Lori; Burstein, David (August 1997), "Spectrophotometry of 237 Stars in 7 Open Clusters", Astronomical Journal, 114: 699–712, arXiv:astro-ph/9705160, Bibcode:1997AJ....114..699C, doi:10.1086/118504, S2CID 15968133.