40 Leonis Minoris

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

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]

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
  1. ^ a b c d e Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Tycho2000 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference Zorec2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Cowley1969 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Osawa1959 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference XHIP was invoked but never defined (see the help page).
  8. ^ a b c Cite error: The named reference David2015 was invoked but never defined (see the help page).
  9. ^ a b c Cite error: The named reference AP1999 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Thevenin1986 was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference Wolff1997 was invoked but never defined (see the help page).
  13. ^ a b Cite error: The named reference Verbunt2010 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Gontcharov2017 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Makarov2005 was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  18. ^ a b Cite error: The named reference Mason2001 was invoked but never defined (see the help page).