Epsilon Mensae
Star in the constellation Mensa
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Epsilon Mensae, Latinized to ε Mensae, is a single[14] star in the southern circumpolar constellation Mensa. It has an apparent magnitude of 5.52,[2] making it faintly visible to the naked eye under ideal conditions. The object has a heliocentric radial velocity of 10.5 km/s,[5] meaning it is receding from the Solar System, and is estimated to be 454 light years away.[1]
 | |
| Observation data Epoch J2000.0 Equinox ICRS | |
|---|---|
| Constellation | Mensa |
| Right ascension | 07h 25m 38.0987s[1] |
| Declination | −79° 05′ 39.088″[1] |
| Apparent magnitude (V) | 5.52±0.01[2] |
| Characteristics | |
| Spectral type | K2/3 III[3] |
| U−B color index | +1.42[4] |
| B−V color index | +1.28[4] |
| Astrometry | |
| Radial velocity (Rv) | 10.5±2.9[5] km/s |
| Proper motion (μ) | RA: −29.197 mas/yr[1] Dec.: +5.181 mas/yr[1] |
| Parallax (π) | 7.1874±0.0449 mas[1] |
| Distance | 454 ± 3 ly (139.1 ± 0.9 pc) |
| Absolute magnitude (MV) | −0.24[6] |
| Details | |
| Mass | 1.15[7] M☉ |
| Radius | 21.94[8] R☉ |
| Luminosity | 170[9] L☉ |
| Surface gravity (log g) | 1.74[7] cgs |
| Temperature | 4,657±122[8] K |
| Metallicity [Fe/H] | −0.31[10] dex |
| Rotational velocity (v sin i) | 1.8±1.4[11] km/s |
| Age | 233[1] Myr |
| Other designations | |
| ε Men, 43 G. Mensae, CPD−78°265, FK5 2583, GC 10055, HD 60816, HIP 36039, HR 2919, SAO 256415[12][13] | |
| Database references | |
| SIMBAD | data |
Epsilon Mensae has a stellar classification of K2/3 III — intermediate between a K2 and K3 giant star.[3] It has 115% the mass of the Sun[7] and an enlarged radius of 21.9 R☉. It shines at 170 times the luminosity of the Sun[9] from its photosphere at an effective temperature of 4,657 K,[8] giving it an orange glow. Epsilon Mensae has a metallicity 49% that of the Sun and is believed to be a member of the young disk population.[10] It spins leisurely with a projected rotational velocity of about 1.8 km/s.[11]