| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Reticulum |
| Right ascension | 03h55m 49.440s[1] |
| Declination | –65° 11′ 12.03″[1] |
| Apparent magnitude (V) | 7.79[2] |
| Characteristics | |
| Spectral type | F8 V[2] |
| B−V color index | 0.554[2] |
| Astrometry | |
| Radial velocity (Rv) | +42.8[3] km/s |
| Proper motion (μ) | RA: +144.020 mas/yr[1] Dec.: +81.550 mas/yr[1] |
| Parallax (π) | 17.928 ± 0.0163 mas[4] |
| Distance | 181.9 ± 0.2 ly (55.78 ± 0.05 pc) |
| Absolute magnitude (MV) | 4.09±0.07[2] |
| Details | |
| Mass | 1.09±0.03[2] M☉ |
| Radius | 1.069±0.041[5] R☉ |
| Luminosity | 1.89[2] L☉ |
| Surface gravity (log g) | 4.17±0.1[5] cgs |
| Temperature | 6,063±50[5] K |
| Metallicity [Fe/H] | −0.11±0.04[2] dex |
| Rotation | 14.4±0.6 d[6] |
| Rotational velocity (v sin i) | 1.0[2] km/s |
| Age | 4.0±1.6[2] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 25171 is a star with an orbiting exoplanet[8] in the southern constellationofReticulum, the reticle. With an apparent visual magnitude of 7.79,[2] this star is too faint to be viewed with the naked eye. However, it is readily visible through a small telescope from the southern hemisphere. Parallax measurements place it at a distance of roughly 182 light-years (56parsecs) from Earth. It is drifting further away with a heliocentric radial velocity of +43 km/s.[3]
Based upon its spectrum, this is an ordinary F-type main sequence star with a stellar classification of F8 V. It is slightly larger than the Sun, with 9% more mass and an 7% greater radius. As such, it is radiating 189% of the Sun's luminosity from its outer atmosphere at an effective temperature of 6,063 K. This gives it the yellow-white hued glow of an F-type star. It appears to be roughly the same age as the Sun; around four billion years.[5][2]
A survey in 2015 ruled out the existence of any stellar companions at projected distances above 26 astronomical units.[9]
The planetary companion was discovered in 2010 with the HARPS instrument, which measured the radial velocity displacement caused by the gravitational perturbation of the star by the planet. This data provided an orbital period of 1,845 days and set a lower bound of the planet's mass at 95% of the mass of Jupiter.[2] The planetary system of HD 25171 is analogous to Solar System in the sense that a gas giant orbiting outside the frost line, far enough to do not destabilize orbits within a circumstellar habitable zone.[10]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >0.956±0.234 MJ | 3.02±0.16 | 1845±15 | 0.08±0.06 | — | — |
