Psi7 Aurigae
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Auriga |
| Right ascension | 06h 50m 45.943s |
| Declination | +41° 46′ 52.43″ |
| Apparent magnitude (V) | 5.02 |
| Characteristics | |
| Spectral type | K3 III |
| U−B color index | +1.35 |
| B−V color index | +1.27 |
| R−I color index | 0.46 |
| Astrometry | |
| Radial velocity (Rv) | +59.53±0.25 km/s |
| Proper motion (μ) | RA: −25.542 mas/yr Dec.: −137.253 mas/yr |
| Parallax (π) | 9.6073±0.1274 mas |
| Distance | 339 ± 5 ly (104 ± 1 pc) |
| Absolute magnitude (MV) | −0.33 |
| Details | |
| Mass | 1.72+1.26 −0.74 M☉ |
| Radius | 19.680 R☉ |
| Luminosity | 162+12 −11 L☉ |
| Surface gravity (log g) | 2.35 cgs |
| Temperature | 4,340±90 K |
| Metallicity [Fe/H] | 0.00 dex |
| Rotational velocity (v sin i) | 10 km/s |
| Age | 700±200 Myr |
| Other designations | |
| ψ7 Aur, 58 Aurigae, BD+41 1536, FK5 2527, GC 8931, HD 49520, HIP 32844, HR 2516, SAO 41380, PPM 49381, WDS J06508+4147A | |
| Database references | |
| SIMBAD | data |
Psi7 Aurigae, is a star in the northern constellation of Auriga. Its name is a Bayer designation that is Latinized from ψ7 Aurigae, and abbreviated Psi7 Aur or ψ7 Aur. This is a dim, naked eye star with an apparent visual magnitude of 5.02. Based upon parallax measurements, it is approximately 339 light-years (104 parsecs) distant from Earth. It is receding from the Sun with a radial velocity of +60 km/s. Psi7 Aur is a probable member of the Hercules stream of co-moving stars.
ψ7 Aur is an evolved giant star with a stellar classification of K3 III. With 1.7 times the mass of the Sun, at an age of about 700 million it has expanded to almost 20 times the Sun's radius. The outer envelope has an effective temperature of 4,340, giving it an orange colour and a classification as a K-type star. Although cooler than the sun, its larger size means that it is more luminous, emitting in total 162 times as much electromagnetic radiation.
It was also known to be part of a much bigger constellation named Telescopium Herschelii before it was unrecognized by the International Astronomical Union (IAU).