| Observation data Epoch J2000.0 Equinox J2000.0 |
|
|---|---|
| Constellation | Gemini |
| Right ascension | 7h 31m 48.40s[1] |
| Declination | +17° 05′ 09.8″[1] |
| Apparent magnitude (V) | +5.45 |
| Characteristics | |
| Spectral type | K2III |
| B−V color index | 1.135 |
| Variable type | “none” |
| Astrometry | |
| Radial velocity (Rv) | –40.2 km/s |
| Proper motion (μ) | RA: 41.29 ± 0.28[1] mas/yr Dec.: -74.80 ± 0.17[1] mas/yr |
| Parallax (π) | 10.32 ± 0.28[1] mas |
| Distance | 316 ± 9 ly (97 ± 3 pc) |
| Absolute magnitude (MV) | 0.62 |
| Details | |
| Radius | 11.62 ± 0.34 R☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 59686 is a 5th magnitude star approximately 316 light years away in the constellation Gemini.
Contents |
It is an orange giant meaning it has ceased fusing hydrogen in its core and on its way to becoming a red giant. The stellar radius is very large (11.6 times that of our Sun).
In November 2003, the planet was announced orbiting the giant star by Mitchell which he used Doppler spectrometer to look for effects on the star caused by the gravitational tug of the orbiting planet. Using the amplitude from the radial velocity method, he calculated the planetary mass as 5.25 Jupiter masses and with period 303 days. However the mass is only minimum because the inclination of the orbit is not known. Using the stellar mass and period, he calculated semimajor axis as 0.911 astronomical units. He found that the shape of the stellar wobble is circular, implying that the planet has zero eccentricity.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity |
|---|---|---|---|---|
| b | >5.25 MJ | 0.911 | 303 | 0 |