32 Leonis Minoris (32 LMi), also known as HD 90840, is a solitary star[14] 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 5.78.[2] The object is located relatively far at a distance of 729 light-years based on Gaia DR3 parallax measurements[1] and it is currently receding with a heliocentric radial velocity of km/s,[6] which is somewhat constrained. At its current distance, 32 LMi's brightness is diminished by 0.14 magnitudes due to interstellar extinction[15] and it has an absolute magnitude of −1.02.[7]

32 Leonis Minoris
Location of 32 LMi on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Leo Minor
Right ascension 10h 30m 06.44761s[1]
Declination +38° 55′ 30.4758″[1]
Apparent magnitude (V) 5.78±0.01[2]
Characteristics
Evolutionary stage subgiant[3]
Spectral type A4 V[4] or A4 III[5]
U−B color index +0.14[5]
B−V color index +0.07[5]
Astrometry
Radial velocity (Rv)2±4.3[6] km/s
Proper motion (μ) RA: −16.446 mas/yr[1]
Dec.: −4.506 mas/yr[1]
Parallax (π)4.4749 ± 0.0527 mas[1]
Distance729 ± 9 ly
(223 ± 3 pc)
Absolute magnitude (MV)−1.02[7]
Details
Mass2.01±0.39[8] M
Radius6.58±0.33[9] R
Luminosity241+41
−35
[3] L
Surface gravity (log g)3.07±0.37[8] cgs
Temperature8,511+79
−78
[3] K
Metallicity [Fe/H]−0.80[10] dex
Rotational velocity (v sin i)70±8[11] km/s
Age465[12] Myr
Other designations
32 LMi, AG+39°1131, BD+39°2357, GC 14417, HD 90840, HIP 51420, HR 4113, SAO 62076[13]
Database references
SIMBADdata

The object has been given several stellar classifications over the years, ranging from main sequence (V) to giant star (III) and A1 to A4. Two of the classifications are A4 V[4] and A4 III.[5] It has 2.01 times the mass of the Sun[8] but at the age of 465 million years,[12] 32 LMi is now on the subgiant branch[8][failed verification] and it has expanded to 6.58 times the radius of the Sun.[9] It radiates 241 times the luminosity of the Sun[3] from its photosphere at an effective temperature of 8,511 K.[3] 32 LMi is metal deficient with an iron abundance only 15.9% that of Sun ([Fe/H] = −0.80)[10] and it spins modestly with a projected rotational velocity of 70 km/s.[11]

References

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  1. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361. S2CID 17128864.
  3. ^ a b c d e Zorec, J.; Royer, F. (January 2012). "Rotational velocities of A-type stars IV: Evolution of rotational velocities". Astronomy & Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691. eISSN 1432-0746. ISSN 0004-6361. S2CID 55586789.
  4. ^ a b 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. Bibcode:1969AJ.....74..375C. doi:10.1086/110819. ISSN 0004-6256. S2CID 121555804.
  5. ^ a b c d Osawa, Kiyoteru (July 1959). "Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of A0 V Stars". The Astrophysical Journal. 130. American Astronomical Society: 159. Bibcode:1959ApJ...130..159O. doi:10.1086/146706. ISSN 0004-637X. S2CID 120004061.
  6. ^ a b Gontcharov, G. A. (November 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. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
  7. ^ a b Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
  8. ^ a b c d Stassun, Keivan G.; Oelkers, Ryan J.; Pepper, Joshua; et al. (20 August 2018). "The TESS Input Catalog and Candidate Target List". The Astronomical Journal. 156 (3): 102. arXiv:1706.00495. Bibcode:2018AJ....156..102S. doi:10.3847/1538-3881/aad050. eISSN 1538-3881. S2CID 73582386. (Erratum: doi:10.3847/1538-3881/AADE86)
  9. ^ a b Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022). "Stellar and substellar companions from Gaia EDR3". Astronomy & Astrophysics. 657: A7. arXiv:2109.10912. Bibcode:2022A&A...657A...7K. doi:10.1051/0004-6361/202142146. eISSN 1432-0746. ISSN 0004-6361.
  10. ^ a b 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. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. eISSN 1432-0746. ISSN 0004-6361. S2CID 131780028.
  11. ^ a b 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. Bibcode:1995ApJS...99..135A. doi:10.1086/192182. ISSN 0067-0049. S2CID 120495962.
  12. ^ a b Gontcharov, G. A. (December 2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771–782. arXiv:1606.08814. Bibcode:2012AstL...38..771G. doi:10.1134/S1063773712120031. eISSN 1562-6873. ISSN 1063-7737. S2CID 118345778.
  13. ^ "32 Leonis Minoris". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved June 29, 2023.
  14. ^ 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. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. eISSN 1365-2966. ISSN 0035-8711. S2CID 14878976.
  15. ^ Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. eISSN 1365-2966. ISSN 0035-8711. S2CID 118879856.