50 Cancri
Star in the constellation Cancer
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± 3 AU from the star, and a cool component at 108± 21 K with a separation of 22± 8 AU .[ 5]
References
^ 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 .
^ 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 .
^ 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 .
^ 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 .
^ 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 .
^ 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 .
^ 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 .
^ "50 Cnc" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2019-03-06 .
^ 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 .
^ 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 .