HD 43197
HD 43197 is a star with an exoplanetary companion in the southern constellation of Canis Major. It has been given the proper name Amadioha, as selected by Nigeria during the NameExoWorlds campaign that celebrated the 100th anniversary of the IAU. Amadioha is the god of thunder in Igbo mythology. It has an apparent visual magnitude of 8.98, meaning this is a ninth magnitude star that is too dim to be visible to the naked eye. The system is located at a distance of 204 light-years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +72 km/s. It made its closest approach some 583,000 years ago when it came to within 87 light-years.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 06h 13m 35.66155s |
| Declination | −29° 53′ 50.1516″ |
| Apparent magnitude (V) | 8.98 |
| Characteristics | |
| Spectral type | G8/K0 IV/V |
| Apparent magnitude (B) | 9.797 |
| Apparent magnitude (J) | 7.658±0.024 |
| Apparent magnitude (H) | 7.328±0.038 |
| Apparent magnitude (K) | 7.203±0.026 |
| B−V color index | 0.817±0.022 |
| Astrometry | |
| Radial velocity (Rv) | 72.45±0.13 km/s |
| Proper motion (μ) | RA: 147.648±0.010 mas/yr Dec.: 16.600±0.011 mas/yr |
| Parallax (π) | 16.0171 ± 0.0106 mas |
| Distance | 203.6 ± 0.1 ly (62.43 ± 0.04 pc) |
| Absolute magnitude (MV) | 5.24 |
| Details | |
| Mass | 1.02±0.02 M☉ |
| Radius | 0.96±0.02 R☉ |
| Luminosity | 0.74±0.01 L☉ |
| Surface gravity (log g) | 4.47±0.03 cgs |
| Temperature | 5,469±35 K |
| Metallicity [Fe/H] | 0.4 dex |
| Rotational velocity (v sin i) | 2.18 km/s |
| Age | 3.1±2.0 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
The stellar classification of this star is G8/K0 IV/V, which may be interpreted to mean the spectrum is intermediate between similar stars of class G8 and K0, and its luminosity class showing a blend of a main sequence star (V) and a subgiant star (IV). It is a weakly active star with a high metallicity, being five halves as much as the Sun. The star is about the same mass and size as the Sun, although the luminosity is only 74% of solar. The star's age is estimated to be at least three billion years and it is modelled to be right at the end of its main sequence life.