HD 97658
HD 97658 is a star with an exoplanetary companion in the equatorial constellation of Leo. The star is too dim to be seen with the naked eye, having an apparent visual magnitude of 7.76. It is located at a distance of 70 light years based on parallax, but is slowly drifting closer with a radial velocity of −1.6 km/s.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 14m 33.1613s |
| Declination | +25° 42′ 37.392″ |
| Apparent magnitude (V) | 7.762±0.012 |
| Characteristics | |
| Evolutionary stage | Main sequence |
| Spectral type | K1V |
| B−V color index | 0.843±0.022 |
| Variable type | Planetary transit variable |
| Astrometry | |
| Radial velocity (Rv) | −1.579±0.0011 km/s |
| Proper motion (μ) | RA: −107.534±0.091 mas/yr Dec.: 48.662±0.090 mas/yr |
| Parallax (π) | 46.412 ± 0.022 mas |
| Distance | 70.27 ± 0.03 ly (21.55 ± 0.01 pc) |
| Absolute magnitude (MV) | 6.14 |
| Details | |
| Mass | 0.773+0.015 −0.018 M☉ |
| Radius | 0.728±0.008 R☉ |
| Luminosity (bolometric) | 0.351±0.007 L☉ |
| Surface gravity (log g) | 4.52 ± 0.06 cgs |
| Temperature | 5212±43 K |
| Metallicity [Fe/H] | −0.30±0.03 dex |
| Rotation | 38.5±1.0 |
| Rotational velocity (v sin i) | 0.92±0.05 km/s |
| Age | 3.9+2.6 −2.03 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an ordinary K-type main-sequence star with a stellar classification of K1V. The star has 77% of the mass and 73% of the radius of the Sun. Estimates of the star's age ranges from four to six billion years. It is spinning with a rotation period of around 39 days and shows a magnetic activity cycle of 9.6 years, which is slightly shorter than the solar cycle. The chromospheric activity is lower than average for stars of this class.
HD 97658 is radiating 35% of the luminosity of the Sun from its photosphere at an effective temperature of 5,212 K. The star has a low metallicity – the atmospheric abundance of elements with a higher atomic number than helium, which explains why it lies 0.46 magnitudes below average for main sequence stars of its type.