Astronomy:34 Leonis Minoris

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Short description: Star in the constellation Leo Minor
34 Leonis Minoris
Leo Minor constellation map.svg
Red circle.svg
Location of 34 LMi on the map (circled)
Observation data
Epoch J2000.0   Equinox (celestial coordinates)
Constellation Leo Minor
Right ascension  10h 33m 30.91104s[1]
Declination +34° 59′ 19.3006″[1]
Apparent magnitude (V) 5.58±0.01[2]
Characteristics
Evolutionary stage subgiant[3]
Spectral type A2 V[4]
U−B color index +0.04[4]
B−V color index +0.02[4]
Astrometry
Radial velocity (Rv)7±10[5] km/s
Proper motion (μ) RA: −28.397[1] mas/yr
Dec.: −3.072[1] mas/yr
Parallax (π)6.3892 ± 0.0706[1] mas
Distance510 ± 6 ly
(157 ± 2 pc)
Absolute magnitude (MV)−1.02[6]
Details
Mass2.40±0.42[7] M
Radius4.85±0.25[8] R
Luminosity323+54−46[3] L
Surface gravity (log g)3.50±0.25[7] cgs
Temperature9,333+152−149[3] K
Metallicity [Fe/H]−0.03[9] dex
Rotational velocity (v sin i)165±8[10] km/s
Age406+134−172[7] Myr
Other designations
11 H. Leonis Minoris,[11] 34 LMi, BD+35°2154, GC 14501, HD 91365, HIP 51685, HR 4137, SAO 62121[12]
Database references
SIMBADdata

34 Leonis Minoris (34 LMi), also known as HD 91365 or 11 H. Leonis Minoris is a solitary star[13] located in the northern constellation Leo Minor. It is faintly visible to the naked eye as a white-hued point of light with an apparent magnitude of 5.58.[2] Gaia DR3 parallax measurements imply a distance of 510 light-years,[1] and it is currently receding with a poorly constrained heliocentric radial velocity of km/s.[5] At its current distance, 34 LMi's brightness is diminished by interstellar extinction of 0.16 magnitudes and it has an absolute magnitude of −1.02.[6]

The object has received several stellar classifications over the years. Most sources generally agree that it is an early A-type main-sequence star with the classes ranging from A0 to A2.[4][14][10] Anne Cowley and colleagues found that 34 LMi has broad or nebulous absorption lines in its spectrum,[15] which could be a result of rapid rotation. However, D. R. Palmer gave a class of A0 IV,[16] indicating that it is an evolved A-type subgiant.[16] Richard O. Gray and Robert F. Garrison found a class of A1 III-IV, indicating that it has a luminosity class intermediate between a subgiant and giant star.[17]

34 LMi has 2.4 times the mass of the Sun[7] and an enlarged radius of 4.85 R.[8] It radiates 323 times the luminosity of the Sun from its photosphere at an effective temperature of 9,333 K.[3] At the age of 406 million years[7] 34 LMi is 1.9% past its main sequence lifetime,[3] meaning that it has evolved to the subgiant branch. The star has a near-solar metallicity at [Fe/H] = −0.03 (93% solar).[9] Like many hot stars 34 LMi spins rapidly, having a projected rotational velocity of 165 km/s.[10]

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 Oja, T. (August 1991). "UBV photometry of stars whose positions are accurately known. VI.". Astronomy and Astrophysics Supplement Series 89: 415. ISSN 0365-0138. Bibcode1991A&AS...89..415O. 
  3. 3.0 3.1 3.2 3.3 3.4 Zorec, J.; Royer, F. (January 2012). "Rotational velocities of A-type stars IV: Evolution of rotational velocities". Astronomy & Astrophysics 537: A120. doi:10.1051/0004-6361/201117691. ISSN 0004-6361. Bibcode2012A&A...537A.120Z. 
  4. 4.0 4.1 4.2 4.3 Osawa, Kiyoteru (July 1959). "Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of A0 V Stars.". The Astrophysical Journal (American Astronomical Society) 130: 159. doi:10.1086/146706. ISSN 0004-637X. Bibcode1959ApJ...130..159O. 
  5. 5.0 5.1 Kharchenko, N.V.; Scholz, R.-D.; Piskunov, A.E.; Röser, S.; Schilbach, E. (November 2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten 328 (9): 889–896. doi:10.1002/asna.200710776. ISSN 0004-6337. Bibcode2007AN....328..889K. 
  6. 6.0 6.1 Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. ISSN 1063-7737. Bibcode2012AstL...38..331A. 
  7. 7.0 7.1 7.2 7.3 7.4 Gullikson, Kevin; Kraus, Adam; Dodson-Robinson, Sarah (25 July 2016). "The Close Companion Mass-ratio Distribution of Intermediate-mass Stars". The Astronomical Journal 152 (2): 40. doi:10.3847/0004-6256/152/2/40. Bibcode2016AJ....152...40G. 
  8. 8.0 8.1 Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants". Astronomy & Astrophysics 426 (1): 297–307. doi:10.1051/0004-6361:20035930. ISSN 0004-6361. Bibcode2004A&A...426..297K. 
  9. 9.0 9.1 Anders, F. et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics 628: A94. doi:10.1051/0004-6361/201935765. ISSN 0004-6361. Bibcode2019A&A...628A..94A. 
  10. 10.0 10.1 10.2 Abt, Helmut A.; Morrell, Nidia I. (July 1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". The Astrophysical Journal Supplement Series 99: 135. doi:10.1086/192182. ISSN 0067-0049. Bibcode1995ApJS...99..135A. 
  11. Verbunt, F.; van Gent, R. H. (June 2010). "The star catalogue of Hevelius: Machine-readable version and comparison with the modern Hipparcos Catalogue". Astronomy and Astrophysics 516: A29. doi:10.1051/0004-6361/201014003. ISSN 0004-6361. Bibcode2010A&A...516A..29V. 
  12. "34 Leonis Minoris". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=34+Leonis+Minoris. 
  13. Eggleton, P. P.; Tokovinin, A. A. (11 September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society 389 (2): 869–879. doi:10.1111/j.1365-2966.2008.13596.x. ISSN 0035-8711. Bibcode2008MNRAS.389..869E. 
  14. Cucchiaro, A.; Macau-Hercot, D.; Jaschek, M.; Jaschek, C. (July 1978). "Spectral classification from the ultraviolet line features of S2/68 spectra. III. Early A-type stars.". Astronomy and Astrophysics Supplement Series 33: 15–26. ISSN 0365-0138. Bibcode1978A&AS...33...15C. 
  15. Cowley, A.; Cowley, C.; Jaschek, M.; Jaschek, C. (April 1969). "A study of the bright stars. I. A catalogue of spectral classifications.". The Astronomical Journal 74: 375. doi:10.1086/110819. ISSN 0004-6256. Bibcode1969AJ.....74..375C. 
  16. 16.0 16.1 Palmer, D. R.; Walker, E. N.; Jones, D. H. P.; Wallis, R. E. (1968). "The radial velocities spectral types and projected rotational velocities of 633 bright northern A stars.". Royal Greenwich Observatory Bulletins 135: 385. Bibcode1968RGOB..135..385P. 
  17. Gray, R. O.; Garrison, R. F. (December 1987). "The early A type stars - Refined MK classification, confrontation with Stroemgren photometry, and the effects of rotation". The Astrophysical Journal Supplement Series (American Astronomical Society) 65: 581. doi:10.1086/191237. ISSN 0067-0049. Bibcode1987ApJS...65..581G.