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50 Cancri
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Cancer
Right ascension 08h 46m 56.01919s [1]
Declination +12° 06′ 35.8305″ [1]
Apparent magnitude (V) 5.89 [2]
Characteristics
Evolutionary stage main sequence
Spectral type A1 Vp [3]
B−V color index 0.120±0.005 [2]
Variable type None [4]
Astrometry
Radial velocity (Rv)23.3±2.9 [2] km/s
Proper motion (μ) RA: −63.773 [1]  mas/ yr
Dec.: −50.694 [1]  mas/ yr
Parallax (π)17.7961 ± 0.0792  mas [1]
Distance183.3 ± 0.8  ly
(56.2 ± 0.3  pc)
Absolute magnitude (MV)+1.82±0.01 [4]
Details
Mass2.1 [5]  M
Luminosity10.8±0.21 [5]  L
Surface gravity (log g)4.40 [6]  cgs
Temperature8,340±48 [5]  K
Rotational velocity (v sin i)18 [7] km/s
Age264 [6]  Myr
Other designations
A2 Cancri, 50 Cnc, BD+12°1904, HD 74873, HIP 43121, HR 3481, SAO 98117 [8]
Database references
SIMBAD data

50 Cancri is a single [9] star in the zodiac constellation of Cancer, located 183  light years away from the Sun. [1] It has the Bayer designation A2 Cancri; 50 Cancri is the Flamsteed designation. It is faintly visible to the naked eye as a white-hued star with an apparent visual magnitude of 5.89. [2] The star is moving away from the Earth with a heliocentric radial velocity of 23 km/s, having come to within 118 light-years some 1.2 million years ago. [2]

This is a chemically peculiar A-type main-sequence star with a stellar classification of A1 Vp. [3] It is a Lambda Boötis star displaying strongly-depleted iron peak and alpha process elements, but otherwise relatively normal solar abundances. [5] The star shows no variability down to a detection limit of 1.6 millimagnitudes. [10] It is 264 [6] million years old with a relatively low projected rotational velocity of 18 km/s. [7] 50 Cancri has 2.1 [5] times the mass of the Sun and is radiating 11 [5] times the Sun's luminosity from its photosphere at an effective temperature of 8,340 K. [5]

50 Cancri has an infrared excess, which most likely indicates a debris disk in orbit around the host star. A blackbody model of the emission shows a two component fit, with the warm section having a temperature of 246±91 K at a radius of 4±AU from the star, and a cool component at 108±21 K with a separation of 22±8 AU. [5]

References

  1. ^ a b c d e f 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 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 Abt, Helmut A.; Morrell, Nidia I. (1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars", Astrophysical Journal Supplement, 99: 135, Bibcode: 1995ApJS...99..135A, doi: 10.1086/192182.
  4. ^ a b Paunzen, E.; et al. (November 2002), "The status of Galactic field λ Bootis stars in the post-Hipparcos era", Monthly Notices of the Royal Astronomical Society, 336 (3): 1030–1042, arXiv: astro-ph/0207488, Bibcode: 2002MNRAS.336.1030P, doi: 10.1046/j.1365-8711.2002.05865.x, S2CID  2389489.
  5. ^ a b c d e f g h Draper, Z. H.; et al. (2016), "IR excesses around nearby Lambda Boo stars are caused by debris discs rather than ISM bow waves", Monthly Notices of the Royal Astronomical Society, 456 (1): 459, arXiv: 1511.05919, Bibcode: 2016MNRAS.456..459D, doi: 10.1093/mnras/stv2696, S2CID  118343020.
  6. ^ a b c David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv: 1501.03154, Bibcode: 2015ApJ...804..146D, doi: 10.1088/0004-637X/804/2/146, S2CID  33401607.
  7. ^ a b Zorec, J.; et al. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics, 537: A120, arXiv: 1201.2052, Bibcode: 2012A&A...537A.120Z, doi: 10.1051/0004-6361/201117691, S2CID  55586789.
  8. ^ "50 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-06.
  9. ^ De Rosa, R. J.; et al. (2014), "The VAST Survey - III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216, arXiv: 1311.7141, Bibcode: 2014MNRAS.437.1216D, doi: 10.1093/mnras/stt1932, S2CID  88503488.
  10. ^ Paunzen, E.; et al. (September 2002), "On the Period-Luminosity-Colour-Metallicity relation and the pulsational characteristics of lambda Bootis type stars", Astronomy and Astrophysics, 392 (2): 515–528, arXiv: astro-ph/0207494, Bibcode: 2002A&A...392..515P, doi: 10.1051/0004-6361:20020854, S2CID  54666586.