HIP 57274
HIP 57274 is a star in the northern circumpolar constellation of Ursa Major with a system of three planets. It is invisible to the naked eye, having an apparent visual magnitude of 8.96. The distance to this system is 84.4 light years based on stellar parallax, and it is drifting further away with a radial velocity of +30 km/s. The star has a relatively high rate of proper motion, traversing the celestial sphere at the rate of 0.382 arcsecond/year.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 11h 44m 40.9643s |
| Declination | +30° 57′ 33.4509″ |
| Apparent magnitude (V) | 8.96 |
| Characteristics | |
| Spectral type | K5 V |
| U−B color index | +1.06 |
| B−V color index | +1.111±0.016 |
| Astrometry | |
| Radial velocity (Rv) | +29.76±0.35 km/s |
| Proper motion (μ) | RA: −27.069±0.081 mas/yr Dec.: −381.708±0.079 mas/yr |
| Parallax (π) | 38.6381 ± 0.0499 mas |
| Distance | 84.4 ± 0.1 ly (25.88 ± 0.03 pc) |
| Absolute magnitude (MV) | 6.89 |
| Details | |
| Mass | 0.73±0.05 M☉ |
| Radius | 0.68±0.03 R☉ |
| Luminosity | 0.19±0.01 L☉ |
| Surface gravity (log g) | 4.71±0.1 cgs |
| Temperature | 4,640±100 K |
| Metallicity [Fe/H] | +0.09±0.05 dex |
| Rotation | 45 d |
| Rotational velocity (v sin i) | 0.5±0.5 km/s |
| Age | 7.87±5 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| ARICNS | data |
This is an ordinary K-type main-sequence star with a stellar classification of K5V. It appears to be older than the Sun with an age of roughly eight billion years and is spinning slowly with a projected rotational velocity of under 1 km/s. The star has 73% of the mass of the Sun and 68% of the Sun's radius. The abundance of elements heavier than helium is about the same or slightly higher than in the Sun. The star is radiating just 19% of the luminosity of the Sun from its photosphere at an effective temperature of 4,640 K.