| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Libra |
| Right ascension | 15h34m 10.70209s[1] |
| Declination | −10° 03′ 52.3063″[1] |
| Apparent magnitude (V) | 4.61[2] |
| Characteristics | |
| Evolutionary stage | subgiant[3] |
| Spectral type | K1III–IV[4] |
| B−V color index | 1.00±0.03[2] |
| Astrometry | |
| Radial velocity (Rv) | +49.25±0.08[5] km/s |
| Proper motion (μ) | RA: +307.63[1] mas/yr Dec.: −234.51[1] mas/yr |
| Parallax (π) | 34.57 ± 0.22 mas[1] |
| Distance | 94.3 ± 0.6 ly (28.9 ± 0.2 pc) |
| Absolute magnitude (MV) | 2.30[2] |
| Details[5] | |
| Mass | 1.38±0.10 M☉ |
| Radius | 5.09±0.19 R☉ |
| Luminosity | 13.5+1.6 −1.5 L☉ |
| Surface gravity (log g) | 3.19±0.06 cgs |
| Temperature | 4,836±22 K |
| Metallicity [Fe/H] | 0.02±0.04 dex |
| Rotational velocity (v sin i) | 2.02±0.33 km/s |
| Age | 3.39±0.80 Gyr |
| Other designations | |
37 Lib, BD−09°4171, FK5 1409, GC 20914, HD 138716, HIP 76219, HR 5777, SAO 140609[6] | |
| Database references | |
| SIMBAD | data |
37 Librae is a single[7] star in the southern zodiac constellationofLibra. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.61.[2] The star is located 94 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +49 km/s.[5]
This is an evolving subgiant star[3] with a stellar classification of K1 III–IV,[4] where the luminosity class indicates the spectrum displays blended traits of a subgiant and a giant star. It is an estimated 3.4 billion years old with 1.4 times the mass of the Sun. Having the supply of hydrogen at its core all but exhausted, the star is starting to expand; currently it has five times the girth of the Sun. It is radiating 13.5 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,836 K.[5]
