Astronomy:Mu Leporis

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Short description: Star in the constellation Lepus
μ Leporis
Lepus constellation map.svg
Red circle.svg
Location of μ Leporis (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Lepus
Right ascension  05h 12m 55.90296s[1]
Declination −16° 12′ 19.6686″[1]
Apparent magnitude (V) 3.259[2]
Characteristics
Spectral type B9 IV:HgMn[3]
U−B color index −0.357[2]
B−V color index −0.096[2]
Variable type Suspected α2 CVn[4]
Astrometry
Radial velocity (Rv)+27.7[5] km/s
Proper motion (μ) RA: +45.702[1] mas/yr
Dec.: −16.017[1] mas/yr
Parallax (π)19.1775 ± 0.3265[1] mas
Distance170 ± 3 ly
(52.1 ± 0.9 pc)
Absolute magnitude (MV)−0.49[6]
Details
Mass3.45[7] M
Radius3.39±0.16[4] R
Luminosity251[6] L
Surface gravity (log g)3.85[8] cgs
Temperature12,820±436[7] K
Metallicity [Fe/H]−0.05[8] dex
Rotational velocity (v sin i)16±0.5[4] km/s
Age125[7] Myr
Other designations
μ Lep, 5 Lep, BD−16°1072, FK5 1144, HD 33904, HIP 24305, HR 1702, SAO 150237[9]
Database references
SIMBADdata

Mu Leporis, Latinized from μ Leporis, is a star in the southern constellation of Lepus. The apparent visual magnitude is 3.259, making the star visible to the naked eye at night from the southern hemisphere. Parallax measurements yield an estimated distance of 170 light-years (52 parsecs) from the Earth. It is moving further from the Sun with a radial velocity of +27.7 km/s.

The stellar classification of this star is B9 IV:HgMn,[3] although the ':' indicates an uncertain spectral value. The luminosity class of IV indicates that this is a subgiant that has exhausted the hydrogen at its core and it is in the process of evolving into a giant star. At present it has about 3.4 times the Sun's radius,[4] 3.45[7] times the mass of the Sun, and is radiating 251[6] times the Sun's luminosity from its photosphere at an effective temperature of 12,800 K.[8]

A light curve for Mu Leporis, plotted from TESS data[10]

Mu Leporis is a suspected Alpha² Canum Venaticorum variable with a period of 2.933 days.[11] The stellar spectrum of this star shows overabundances of mercury and manganese, as indicated by the HgMn in the stellar class.[4] X-ray emission has been detected coming from a location at an angular separation of 0.93 arcseconds from this star. At the estimated distance of Mu Leporis, this equals a projected distance of 52 Astronomical Units. The source may be a stellar companion: either a star that has not yet reached the main sequence or a small, low-temperature star. The X-ray luminosity of this object is (4.4 ± 0.1) × 10 29 erg s−1.[12]

References

  1. 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. 2.0 2.1 2.2 Gutierrez-Moreno, Adelina et al. (1966). "A System of photometric standards". Publications of the Department of Astronomy University of Chile (Publicaciones Universidad de Chile, Department de Astronomy) 1: 1–17. Bibcode1966PDAUC...1....1G. 
  3. 3.0 3.1 Houk, N.; Smith-Moore, M. (1988). Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars, Volume 4, Declinations -26°.0 to -12°.0. Ann Arbor, MI: Department of Astronomy, University of Michigan. Bibcode1988mcts.book.....H. 
  4. 4.0 4.1 4.2 4.3 4.4 Kochukhov, O. et al. (October 2011). "No magnetic field in the spotted HgMn star μ Leporis". Astronomy & Astrophysics 534: L13. doi:10.1051/0004-6361/201117970. Bibcode2011A&A...534L..13K. 
  5. Wilson, Ralph Elmer (1953). "General Catalogue of Stellar Radial Velocities". Carnegie Institute Washington D.C. Publication (Washington: Carnegie Institution of Washington). Bibcode1953GCRV..C......0W. 
  6. 6.0 6.1 6.2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A. 
  7. 7.0 7.1 7.2 7.3 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. doi:10.1088/0004-637X/804/2/146. Bibcode2015ApJ...804..146D. 
  8. 8.0 8.1 8.2 Smith, K. C.; Dworetsky, M. M. (July 1993). "Elemental Abundances in Normal Late B-Stars and Hgmn-Stars from Co-Added IUE Spectra - Part One - Iron Peak Elements". Astronomy and Astrophysics 274 (2): 335. Bibcode1993A&A...274..335S. 
  9. "mu. Lep -- Variable Star of alpha2 CVn type". SIMBAD. Centre de Données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-id?Ident=HD+33904. Retrieved 2012-01-09. 
  10. "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html. 
  11. Kochukhov, O.; Khalack, V.; Kobzar, O.; Neiner, C.; Paunzen, E.; Labadie-Bartz, J.; David-Uraz, A. (October 2021). "TESS survey of rotational and pulsational variability of mercury–manganese stars". Monthly Notices of the Royal Astronomical Society 506 (4): 5328–5344. doi:10.1093/mnras/stab2107. 
  12. Behar, Ehud et al. (September 2004). "Resolving X-Ray Sources from B Stars Spectroscopically: The Example of μ Leporis". The Astrophysical Journal 612 (1): L65–L68. doi:10.1086/424485. Bibcode2004ApJ...612L..65B. 

External links