7 Leonis Minoris
G-type giant in the constellation Leo Minor
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7 Leonis Minoris (7 LMi) is a star located in the northern constellation Leo Minor. It is also designated as HD 82087 and HR 3764. 7 LMi is faintly visible to the naked eye as a yellow-hued point of light with an apparent magnitude of 5.86.[2] Gaia DR3 parallax measurements imply a distance of 462 light-years[1] and it is currently receding with a heliocentric radial velocity of 1.7 km/s.[6] At its current distance, 7 LMi's brightness is diminished by 0.12 magnitudes due to interstellar extinction[13] and it has an absolute magnitude of −0.03.[7]
 | |
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Leo Minor |
| Right ascension | 09h 30m 43.22705s[1] |
| Declination | +33° 39′ 20.5700″[1] |
| Apparent magnitude (V) | 5.86±0.01[2] |
| Characteristics | |
| Evolutionary stage | horizontal branch[3] |
| Spectral type | G9 III[4] |
| B−V color index | +1.05[5] |
| Astrometry | |
| Radial velocity (Rv) | 1.7±0.9[6] km/s |
| Proper motion (μ) | RA: −23.939 mas/yr[1] Dec.: −48.160 mas/yr[1] |
| Parallax (π) | 7.0542±0.1338 mas[1] |
| Distance | 462 ± 9 ly (142 ± 3 pc) |
| Absolute magnitude (MV) | −0.03[7] |
| Details | |
| Mass | 2.74+0.24 −0.25[3] M☉ |
| Radius | 13.41±0.68[8] R☉ |
| Luminosity | 96.0+3.3 −3.6[1] L☉ |
| Surface gravity (log g) | 2.49+0.07 −0.06[3] cgs |
| Temperature | 4,923±122[9] K |
| Metallicity [Fe/H] | −0.03±0.10[10] dex |
| Rotational velocity (v sin i) | 0.24[11] km/s |
| Age | 575+201 −139[3] Myr |
| Other designations | |
| 7 LMi, AG+33°953, BD+34°1999, FK5 2755, GC 13112, HD 82087, HIP 46652, HR 3764, SAO 61529, CCDM J09307+3339A, WDS J09307+3339A, TIC 8855140[12] | |
| Database references | |
| SIMBAD | data |
There have been disagreements on the object's stellar classification. 7 LMi is either a G-type giant star with a class of either G8 or G9 III,[4] or it is a K-type giant with a class of K0 III.[14] It is most likely on the horizontal branch (95% fit),[3] generating energy via helium fusion at its core. It has 2.74 times the mass of the Sun but at the age of 575 million years,[3] it has expanded to 13.41 times the radius of the Sun.[8] It radiates 96 times the luminosity of the Sun[1] from its enlarged photosphere at an effective temperature of 4,923 K.[9] 7 LMi has a near solar metallicity at [Fe/H] = −0.03[10] and it spins very slowly with a projected rotational velocity of 0.24 km/s.[11]
7 LMi has two visual companions. AG +33°954 is a background star located much farther away than 7 LMi[15] and it is a close spectroscopic binary itself.[16]
| Companion | Stellar classification | PA (deg) | Separation (arcsec) | Apparent magnitude |
|---|---|---|---|---|
| AG +33°954 (B) | G8 IV-V[4] | 125 | 61.3 | 9.7 |
| C | G5 V[4] | 217 | 95.9 | 11.6 |