7 Leonis Minoris

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]

7 Leonis Minoris
Location of 7 LMi on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
ConstellationLeo Minor
Right ascension09h 30m 43.22705s[1]
Declination+33° 39′ 20.5700″[1]
Apparent magnitude (V)5.86±0.01[2]
Characteristics
Evolutionary stagehorizontal branch[3]
Spectral typeG9 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]
Distance462 ± 9 ly
(142 ± 3 pc)
Absolute magnitude (MV)−0.03[7]
Details
Mass2.74+0.24
−0.25
[3] M
Radius13.41±0.68[8] R
Luminosity96.0+3.3
−3.6
[1] L
Surface gravity (log g)2.49+0.07
−0.06
[3] cgs
Temperature4,923±122[9] K
Metallicity [Fe/H]−0.03±0.10[10] dex
Rotational velocity (v sin i)0.24[11] km/s
Age575+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
SIMBADdata

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]

7 Leonis Minoris' companions[17]
CompanionStellar classificationPA (deg)Separation (arcsec)Apparent magnitude
AG +33°954 (B)G8 IV-V[4]12561.39.7
CG5 V[4]21795.911.6

References