Pi Mensae
| Observation data Epoch J2000.0 Equinox J2000.0 |
|
|---|---|
| Constellation | Mensa |
| Right ascension | 05h 37m 09.89s [1] |
| Declination | –80° 28′ 08.8″ [1] |
| Apparent magnitude (V) | +5.67 |
| Characteristics | |
| Spectral type | G1IV |
| U−B color index | 0.11 |
| B−V color index | 0.60 |
| V−R color index | 0.31 |
| R−I color index | 0.29 |
| Variable type | none |
| Astrometry | |
| Radial velocity (Rv) | +9.4 km/s |
| Proper motion (μ) | RA: 312.01 ± 0.24 [1] mas/yr Dec.: 1050.38 ± 0.26 [1] mas/yr |
| Parallax (π) | 54.60 ± 0.21[1] mas |
| Distance | 59.7 ± 0.2 ly (18.32 ± 0.07 pc) |
| Absolute magnitude (MV) | +4.37 |
| Details | |
| Mass | 1.1 M☉ |
| Radius | 2.1 ± 0.6 R☉ |
| Luminosity | 4.73 L☉ |
| Surface gravity (log g) | 3.33 cgs |
| Temperature | 5888 K |
| Metallicity | 0.09 (123%) |
| Rotation | ? |
| Age | 3.83 × 109 years |
| Other designations | |
Pi Mensae (π Men) is a yellow subgiant star in the constellation of Mensa. This star has a high proper motion. The apparent magnitude is 5.67, which can be visible to the naked eye in exceptionally dark, clear skies. It is nearly 60 ly away. The star dwarfs the Sun in terms of mass, size, luminosity, temperature, and metallicity and is about 730 million years younger. It ranks 100th on the list of top 100 target stars for the planned Terrestrial Planet Finder mission to search for Earth-like planets.
Planetary system
On October 15, 2001, an extrasolar planet was found orbiting the star.[2] It is one of the most massive planets ever discovered. It has a very eccentric orbit that takes approximately 2151 days (5.89 years). Because of its eccentricity, and being a massive superjovian that passes through the habitable zone, it would have disrupted the orbits of any Earth-like planets, and possibly thrown them into the star, or out into the interstellar medium.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥10.27 ± 0.84 MJ | 3.38 ± 0.22 | 2151 ± 85 | 0.6405 ± 0.0072 | — | — |
