HD 217107 b
| Discovery | |
|---|---|
| Discovered by | Marcy et al. |
| Discovery site | United States |
| Discovery date | November 24, 1998 |
| Doppler spectroscopy | |
| Orbital characteristics | |
| 0.07359+0.00042 −0.00053 AU | |
| Eccentricity | 0.1284+0.0015 −0.0014 |
| 7.127017(5) d | |
| Inclination | 93°+25° −26° |
| 2455201.109±0.014 | |
| 22.78+0.71 −0.70 | |
| Semi-amplitude | 140.30±0.40 |
| Star | HD 217107 |
| Physical characteristics | |
| Mass | 1.446+0.180 −0.167 MJ |
HD 217107 b is an extrasolar planet approximately 65 light-years away from Earth in the constellation of Pisces (the Fish). The planet was discovered orbiting the star HD 217107 approximately every seven days, classifying the planet as a hot Jupiter. Because of the planet's somewhat eccentric orbit, scientists were able to confirm another planet within the system (HD 217107 c).
In 2025, the use of astrometry allowed the inclination and true mass of the planet to be found. The inclination is nearly edge-on, so the minimum mass is close to the real one.