Pi Chamaeleontis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Chamaeleon |
| Right ascension | 11h 37m 15.63631s |
| Declination | −75° 53′ 47.5626″ |
| Apparent magnitude (V) | 5.64 |
| Characteristics | |
| Spectral type | A9 IV or F1 III |
| U−B color index | −0.01 |
| B−V color index | +0.35 |
| Astrometry | |
| Radial velocity (Rv) | −9.8±3.7 km/s |
| Proper motion (μ) | RA: −127.94 mas/yr Dec.: −1.82 mas/yr |
| Parallax (π) | 24.09±0.33 mas |
| Distance | 135 ± 2 ly (41.5 ± 0.6 pc) |
| Absolute magnitude (MV) | 2.56 |
| Orbit | |
| Period (P) | 223.1845±1.9460 d |
| Semi-major axis (a) | 7.86±0.83 mas |
| Eccentricity (e) | 0.3244±0.1375 |
| Inclination (i) | 104.88±5.52° |
| Details | |
| Mass | 1.52 M☉ |
| Radius | 2.2 R☉ |
| Luminosity | 8 L☉ |
| Surface gravity (log g) | 4.08 cgs |
| Temperature | 6,853±80 K |
| Metallicity [Fe/H] | −0.28 dex |
| Rotational velocity (v sin i) | 50 km/s |
| Age | 1.8±0.1 Gyr |
| Other designations | |
| π Cha, CPD−75°744, FK5 438, HD 101132, HIP 56675, HR 4479, SAO 256857 | |
| Database references | |
| SIMBAD | data |
Pi Chamaeleontis, its name Latinized from π Chamaeleontis, is a binary star system located in the southern circumpolar constellation of Chamaeleon. It is dimly visible to the naked eye with an apparent visual magnitude of 5.64. Parallax measurements by Hipparcos put the system approximately 135 light-years (41.5 parsecs) away. It is drifting closer with a radial velocity of −10 km/s.
The Hipparcos satellite mission derived a 223 d orbit on the basis of its motion caused by an unseen companion. The visible component is an A-type subgiant or F-type giant star with an effective temperature of about 6,900 K. It has an absolute magnitude of 2.56, a mass of 1.52 M☉, and a radius of 2.2 M☉. It is roughly 1.8 billion years old.