72 Leonis is a single[9] variable star in the zodiac constellation of Leo, located roughly 1,000 light years away from the Sun.[1] It has the variable star designation FN Leonis; 72 Leonis is the Flamsteed designation. In Chinese astronomy, 72 Leonis is called 虎賁, Pinyin: Hǔbēn, meaning Emperor’s Bodyguard, because this star is marking itself and stands alone in the Emperor’s Bodyguard asterism, Supreme Palace enclosure mansion (see : Chinese constellation).[10]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Leo |
Right ascension | 11h 15m 12.22709s[1] |
Declination | +23° 05′ 43.8373″[1] |
Apparent magnitude (V) | 4.63[2] |
Characteristics | |
Spectral type | M3 IIb[3] |
B−V color index | 1.657±0.003[4] |
Variable type | LC[5] |
Astrometry | |
Radial velocity (Rv) | 14.76±0.21[4] km/s |
Proper motion (μ) | RA: −25.56[1] mas/yr Dec.: −6.00[1] mas/yr |
Parallax (π) | 3.40 ± 0.65 mas[1] |
Distance | approx. 1,000 ly (approx. 290 pc) |
Absolute magnitude (MV) | −2.69[4] |
Details | |
Mass | 3.11[6] M☉ |
Radius | 195[6] R☉ |
Luminosity | 5,770[7] L☉ |
Surface gravity (log g) | 1.16[6] cgs |
Temperature | 3,613±48[6] K |
Metallicity [Fe/H] | −0.03[6] dex |
Age | 400[6] Myr |
Other designations | |
Database references | |
SIMBAD | data |
This object is visible to the naked eye as a red-hued star with an apparent visual magnitude of 4.56.[4] It is an evolved bright giant with a stellar classification of M3 IIb and was listed as a spectral standard star for that class.[3] The star is classified as an irregular variable of type LC, ranging from Hipparcos magnitude 4.56 down to 4.64.[5] It has a radius 162 to 179[11] times that of the Sun and radiates 5,407[12] times the Sun's luminosity at an effective temperature of around 3,734 K.[13] The star is moving away from the Earth with a heliocentric radial velocity of 15 km/s.[4]