HD 162020
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 17h 50m 38.35575s |
| Declination | −40° 19′ 06.0723″ |
| Apparent magnitude (V) | 9.10 |
| Characteristics | |
| Spectral type | K3V |
| B−V color index | 0.964±0.066 |
| Astrometry | |
| Radial velocity (Rv) | −26.55±2.30 km/s |
| Proper motion (μ) | RA: +19.412 mas/yr Dec.: −25.799 mas/yr |
| Parallax (π) | 31.8624±0.0622 mas |
| Distance | 102.4 ± 0.2 ly (31.38 ± 0.06 pc) |
| Absolute magnitude (MV) | 6.76 |
| Orbit | |
| Period (P) | 8.4282388+0.0000014 −0.0000026 d |
| Semi-major axis (a) | 0.0859±0.0010 AU |
| Eccentricity (e) | 0.28126±0.00057 |
| Inclination (i) | 177.273+0.030 −0.027° |
| Longitude of the node (Ω) | 288.93+0.67 −0.73° |
| Periastron epoch (T) | 2457393.1874+0.0026 −0.0023 |
| Argument of periastron (ω) (secondary) | 28.70+0.13 −0.12° |
| Semi-amplitude (K1) (primary) | 1.8112+0.0013 −0.0016 km/s |
| Details | |
| Mass | 0.797±0.042 M☉ |
| Radius | 0.770±0.017 R☉ |
| Luminosity | 0.413+0.056 −0.050 L☉ |
| Surface gravity (log g) | 4.567±0.028 cgs |
| Temperature | 5,270+190 −180 K |
| Metallicity [Fe/H] | −0.18+0.17 −0.19 dex |
| Rotational velocity (v sin i) | 1.9 km/s |
| Age | 5.7±4.7 Gyr 3.1±2.7 Gyr |
| HD 162020 b | |
| Mass | 0.39±0.02 M☉ |
| Mass | 410.8+5.8 −5.3 MJup |
| Other designations | |
| CD−40°11894, HD 162020, HIP 87330, PPM 763039 | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HD 162020 is a star in the southern constellation of Scorpius with a likely red dwarf companion. It has an apparent visual magnitude of 9.10, which is too faint to be visible to the naked eye. The distance to this system is 102 light-years (31 parsecs) based on stellar parallax. It is drifting closer to the Sun with a radial velocity of −27 km/s, and is predicted to come to within ~18 light-years in 1.1 million years.
This is an ordinary K-type main-sequence star with a stellar classification of K3V. The age estimate is poorly constrained but it appears to have an intermediate age of several billion years. However, the activity level suggests a younger star; the rotation rate of the star may have been increased through synchronization with the companion, resulting in a higher than normal activity for its age. X-ray emission has been detected from this star.
HD 162020 has 74% of the mass of the Sun and 73% of the Sun's radius. The abundance of iron is roughly the same as the Sun, suggesting a similar metallicity. It is radiating just 25.8% of the luminosity of the Sun from its photosphere at an effective temperature of 4,801 K. The star is spinning with a projected rotational velocity of 1.9 km/s.