40 Leonis Minoris

Summary

40 Leonis Minoris (40 LMi) is a white hued star located in the northern constellation Leo Minor. It is rarely called 14 H. Leonis Minoris, which is the designation given by Polis astronomer Johann Hevelius.[13]

40 Leonis Minoris
Location of 40 LMi (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Leo Minor
Right ascension 10h 43m 01.88241s[1]
Declination +26° 19′ 32.0287″[1]
Apparent magnitude (V) 5.51±0.01[2]
Characteristics
Evolutionary stage main sequence star[3]
Spectral type A4 Vn[4]
U−B color index +0.19[5]
B−V color index +0.17[5]
Astrometry
Radial velocity (Rv)10±4.3[6] km/s
Proper motion (μ) RA: −98.971 mas/yr[1]
Dec.: −65.543 mas/yr[1]
Parallax (π)21.2215 ± 0.0816 mas[1]
Distance153.7 ± 0.6 ly
(47.1 ± 0.2 pc)
Absolute magnitude (MV)+2.23[7]
Details
Mass1.69[8] M
Radius1.54±0.04[9] R
Luminosity14.3+1.8
−1.6
[3] L
Surface gravity (log g)4.30±0.04[9] cgs
Temperature7834±108[10] K
Metallicity [Fe/H]−0.15[11] dex
Rotational velocity (v sin i)211[12] km/s
Age207[8] Myr
Other designations
14 H. Leonis Minoris,[13] 40 LMi, AG+26°1125, BD+27°1927, GC 14730, HD 92769, HIP 52422, HR 4189, SAO 81485, WDS J10430+2620A[14]
Database references
SIMBADdata

It has an apparent magnitude of 5.51,[2] making it faintly visible to the naked eye. The object is located relatively close at a distance of 154 light years based on Gaia DR3 parallax measurements[1] but is receding with a somewhat constrained heliocentric radial velocity of 10 km/s.[6] At 40 LMi's current distance, its brightness is diminished by only 0.02 magnitudes due to interstellar dust.[15]

40 LMi is a chemically peculiar A-type main-sequence star with a stellar classification of A4 Vn.[4] This indicates that it is an A4 dwarf with nebulous absorption lines due to rapid rotation. It has 1.69 times the mass of the Sun[8] and 1.54 times its girth.[9] It radiates 14.3 times the luminosity of the Sun[3] from its photosphere at an effective temperature of 7,834 K.[10] The star is estimated to be 207 million years old, having completed 54.6% of its main sequence lifetime.[3] 40 LMi is slightly metal deficient and spins rapidly with a projected rotational velocity of 211 km/s.[12]

This star was part of a 2005 survey regarding proper motions from the Hipparcos satellite.[16] Its proper motion varied, indicating that an unseen companion may cause it. This led to Peter P. Eggleton and Andrei Tokovinin classifying it as an astrometric binary.[17] There also 3 optical companions located near 40 LMi. Their relative positions and brightness are listed below.[18]

40 Leonis Minoris' companions[18]
Companion mv PA (°) Year Sep. ()
B 12.6 108 2015 23.8
C 13.5 72 2015 41.6
D 13 285 2015 46.6

References edit

  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.
  3. ^ a b c d 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.
  5. ^ a b Osawa, Kiyoteru (July 1959). "Spectral Classification of 533 B8-A2 Stars and the Mean Absolute Magnitude of a0 V Stars". The Astrophysical Journal. 130: 159. Bibcode:1959ApJ...130..159O. doi:10.1086/146706. eISSN 1538-4357. ISSN 0004-637X.
  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. ^ 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 David, Trevor J.; Hillenbrand, Lynne A. (12 May 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. eISSN 1538-4357.
  9. ^ a b c Allende Prieto, C.; Lambert, D. L. (December 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. ISSN 0004-6361.
  10. ^ a b Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.
  11. ^ Thevenin, F.; Vauclair, S.; Vauclair, G. (September 1986). "A new step towards the explanation of lithium-and beryllium-deficientF stars. I. The field stars". Astronomy and Astrophysics. 166: 216–224. Bibcode:1986A&A...166..216T. ISSN 0004-6361.
  12. ^ a b Wolff, S.; Simon, T. (July 1997). "The Angular Momentum of Main Sequence Stars and Its Relation to Stellar Activity". Publications of the Astronomical Society of the Pacific. 109: 759. Bibcode:1997PASP..109..759W. doi:10.1086/133942. eISSN 1538-3873. ISSN 0004-6280.
  13. ^ a b Verbunt, F.; van Gent, R. H. (June 2010). "The star catalogue of Hevelius". Astronomy and Astrophysics. 516: A29. Bibcode:2010A&A...516A..29V. doi:10.1051/0004-6361/201014003. eISSN 1432-0746. ISSN 0004-6361.
  14. ^ "40 LMi". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved November 15, 2022.
  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.
  16. ^ Makarov, V. V.; Kaplan, G. H. (May 2005). "Statistical Constraints for Astrometric Binaries with Nonlinear Motion". The Astronomical Journal. 129 (5): 2420–2427. Bibcode:2005AJ....129.2420M. doi:10.1086/429590. eISSN 1538-3881. ISSN 0004-6256.
  17. ^ 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.
  18. ^ a b Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. ISSN 0004-6256.