HD 121504
HD 121504 is a star with an orbiting exoplanet in the southern constellation of Centaurus. It is located at a distance of 136 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of 19.6 km/s. With an apparent visual magnitude of 7.54, this star is too faint to be visible to the naked eye. It shows a high proper motion, traversing the celestial sphere at an angular rate of 0.270 arcsec yr−1.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Centaurus |
| Right ascension | 13h 57m 17.239s |
| Declination | −56° 02′ 24.16″ |
| Apparent magnitude (V) | 7.54 |
| Characteristics | |
| Spectral type | G2V |
| B−V color index | 0.593±0.002 |
| Astrometry | |
| Radial velocity (Rv) | 19.603±0.0004 km/s |
| Proper motion (μ) | RA: −249.354 mas/yr Dec.: −84.570 mas/yr |
| Parallax (π) | 24.0593 ± 0.0269 mas |
| Distance | 135.6 ± 0.2 ly (41.56 ± 0.05 pc) |
| Absolute magnitude (MV) | 4.27 |
| Details | |
| Mass | 1.16±0.02 M☉ |
| Radius | 1.15±0.03 R☉ |
| Luminosity | 1.62±0.04 L☉ |
| Surface gravity (log g) | 4.38±0.03 cgs |
| Temperature | 6,089±47 K |
| Metallicity [Fe/H] | 0.16 dex |
| Rotation | 8.6 days |
| Rotational velocity (v sin i) | 2.6 km/s |
| Age | 1.9±1.0 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
The spectrum of this star presents as an ordinary G-type main-sequence star, a yellow dwarf similar in appearance to the Sun, having a stellar classification of G2V. It is roughly two billion years old and is spinning with a rotation period of 8.6 days. The star has 16% more mass than the Sun and a 15% greater radius. The metallicity (the abundance of elements more massive than helium) is higher than solar. The star is radiating 162% of the luminosity of the Sun from its photosphere at an effective temperature of 6,089 K.
A nearby visual companion, designated as SAO 241323 has been proposed as a component of the system. However, the pair form an optical binary with an angular separation of 34.2″, and in reality this is a white giant star located thousands of light years away.