Star in the constellation Orion
49 Orionis is a single[ 10] star in theequatorial constellation ofOrion . It has theBayer designation d Orionis , while49 Orionis is theFlamsteed designation . This object is visible to the naked eye as a faint, white-hued star with anapparent visual magnitude of 4.80.[ 2] light years away from the Sun based onparallax ,[ 1] radial velocity of −5 km/s.[ 4]
49 Orionis (center) In the past 49 Orionis was reported as aspectroscopic binary and an orbit was computed with aperiod of 445.74 days and aneccentricity of 0.549.[ 11] [ 10]
This object is anA-type main-sequence star with astellar classification of A4Vn,[ 3] lines caused by rapid rotation. It is around 284[ 6] projected rotational velocity of 186 km/s.[ 8] oblate shape with anequatorial bulge that is an estimated 8% larger than the polar radius.[ 12] [ 6] mass of the Sun and double[ 7] Sun's radius . It is radiating 22[ 8] Sun's luminosity from itsphotosphere at aneffective temperature of 8,416 K.[ 6]
^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 atVizieR .^a b c d Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system".CDS/ADC Collection of Electronic Catalogues .2237 .Bibcode :2002yCat.2237....0D . ^a b Gray, R. O.; Garrison, R. F. (July 1989)."The Late A-Type Stars: Refined MK Classification, Confrontation with Stroemgren Photometry, and the Effects of Rotation" .Astrophysical Journal Supplement .70 : 623.Bibcode :1989ApJS...70..623G .doi :10.1086/191349 ^a b Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system".Astronomy Letters .32 (11):759– 771.arXiv :1606.08053 Bibcode :2006AstL...32..759G .doi :10.1134/S1063773706110065 .S2CID 119231169 . ^ 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 . Vizier catalog entry ^a b c d e f g 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 Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures".Astronomy and Astrophysics .352 :555– 562.arXiv :astro-ph/9911002 Bibcode :1999A&A...352..555A . Vizier catalog entry ^a b c d Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars".Astronomy & Astrophysics .537 : A120.arXiv :1201.2052 Bibcode :2012A&A...537A.120Z .doi :10.1051/0004-6361/201117691 .S2CID 55586789 . Vizier catalog entry ^ "49 Ori" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2019-07-29 .^a b 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 . ^ Abt, Helmut A. (June 1965)."The Frequency of Binaries among Normal A-Type Stars" .Astrophysical Journal Supplement .11 : 429.Bibcode :1965ApJS...11..429A .doi :10.1086/190120 ^ Belle, G. T. (2012), "Interferometric observations of rapidly rotating stars",The Astronomy and Astrophysics Review ,20 (1): 51,arXiv :1204.2572 Bibcode :2012A&ARv..20...51V ,doi :10.1007/s00159-012-0051-2 ,S2CID 119273474 .
