Eta Mensae, Latinized from η Mensae, is the Bayer designation for a solitary,[4] orange-hued star in the southern constellation of Mensa. This object has an apparent visual magnitude of 5.47,[2] which is sufficiently luminous to be faintly visible to the naked eye. Based upon an annual parallax shift of 4.88 mas as seen from Earth,[1] this star is located roughly 670 light years from the Sun.
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Mensa |
| Right ascension | 04h 55m 11.20309s[1] |
| Declination | −74° 56′ 12.6705″[1] |
| Apparent magnitude (V) | 5.47[2] |
| Characteristics | |
| Spectral type | K4 III[3][4] |
| U−B color index | +1.82[2] |
| B−V color index | +1.52[2] |
| Astrometry | |
| Proper motion (μ) | RA: +28.27[1] mas/yr Dec.: +61.52[1] mas/yr |
| Parallax (π) | 5.0299 ± 0.0998 mas[5] |
| Distance | 650 ± 10 ly (199 ± 4 pc) |
| Absolute magnitude (MV) | −1.08[6] |
| Details | |
| Luminosity | 616[7] L☉ |
| Surface gravity (log g) | 1.15[8] cgs |
| Temperature | 4,055[7] K |
| Metallicity [Fe/H] | −0.17[8] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an evolved K-type giant star with a stellar classification of K4 III.[3] It is radiating 616 times the Sun's luminosity from its photosphere at an effective temperature of 4,055 K.[7] The star displays an infrared excess that suggests the presence of circumstellar dust.[10][11] Eta Mensae is a probable member of the stream of stars associated with the Hyades cluster.[12]