Jump to content

49 Orionis

From Wikipedia, the free encyclopedia
(Redirected from 49 Ori)
49 Orionis
Location of 49 Orionis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Orion
Right ascension 05h 38m 53.08332s[1]
Declination −07° 12′ 46.1667″[1]
Apparent magnitude (V) 4.80[2]
Characteristics
Evolutionary stage main sequence
Spectral type A4Vn[3]
U−B color index +0.11[2]
B−V color index +0.13[2]
Astrometry
Radial velocity (Rv)−5.30[4] km/s
Proper motion (μ) RA: −15.562[1] mas/yr
Dec.: −50.613[1] mas/yr
Parallax (π)23.1346 ± 0.2801 mas[1]
Distance141 ± 2 ly
(43.2 ± 0.5 pc)
Absolute magnitude (MV)1.52[5]
Details
Mass1.78[6] M
Radius2.0[7] R
Luminosity22[8] L
Surface gravity (log g)4.06[6] cgs
Temperature8,416±286[6] K
Rotational velocity (v sin i)186[8] km/s
Age284[6] Myr
Other designations
d Ori, 49 Ori, BD−07°1142, GC 7039, GJ 9187, HD 37507, HIP 26563, HR 1937, SAO 132411[9]
Database references
SIMBADdata

49 Orionis is a single[10] star in the equatorial constellation of Orion. It has the Bayer designation d Orionis, while 49 Orionis is the Flamsteed designation. This object is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of 4.80.[2] It is located 141 light years away from the Sun based on parallax,[1] but is drifting closer with a radial velocity of −5 km/s.[4]

49 Orionis (center)

In the past 49 Orionis was reported as a spectroscopic binary and an orbit was computed with a period of 445.74 days and an eccentricity of 0.549.[11] But it was later determined to be single.[10]

This object is an A-type main-sequence star with a stellar classification of A4Vn,[3] where the 'n' suffix indicates broadened "nebulous" lines caused by rapid rotation. It is around 284[6] million years old with a projected rotational velocity of 186 km/s.[8] This spin is giving the star an oblate shape with an equatorial bulge that is an estimated 8% larger than the polar radius.[12] The star has 1.8[6] times the mass of the Sun and double[7] the Sun's radius. It is radiating 22[8] times the Sun's luminosity from its photosphere at an effective temperature of 8,416 K.[6]

References

[edit]
  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 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.
  3. ^ 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.
  4. ^ 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.
  5. ^ 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
  6. ^ 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.
  7. ^ 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
  8. ^ 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
  9. ^ "49 Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-07-29.
  10. ^ 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.
  11. ^ 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.
  12. ^ 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.