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]
  | |
| 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] |
| Distance | 153.7 ± 0.6 ly (47.1 ± 0.2 pc) |
| Absolute magnitude (MV) | +2.23[7] |
| Details | |
| Mass | 1.69[8] M☉ |
| Radius | 1.54±0.04[9] R☉ |
| Luminosity | 14.3+1.8 −1.6[3] L☉ |
| Surface gravity (log g) | 4.30±0.04[9] cgs |
| Temperature | 7834±108[10] K |
| Metallicity [Fe/H] | −0.15[11] dex |
| Rotational velocity (v sin i) | 211[12] km/s |
| Age | 207[8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
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]
| 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 |