Gliese 876 e
An artist's impression of Gliese 876 e | |
| Discovery | |
|---|---|
| Discovered by | Rivera et al. |
| Discovery date | June 23, 2010 |
| Doppler spectroscopy | |
| Orbital characteristics | |
| Epoch BJD 2,450,602.09311 | |
| 0.3355+0.0019 −0.0011 AU | |
| Eccentricity | 0.0545+0.0069 −0.022 |
| 123.55+1.0 −0.59 d | |
| 50.3°+46° −86.8° | |
| Inclination | 56.7°+1.0° −0.99° |
| 240°+23° −50° | |
| Semi-amplitude | 3.49±0.23 m/s |
| Star | Gliese 876 |
| Physical characteristics | |
| Mass | 16.0±1.0 M🜨 |
Gliese 876 e is an exoplanet orbiting the star Gliese 876 in the constellation of Aquarius. It is in a 1:2:4 Laplace resonance with the planets Gliese 876 c and Gliese 876 b: for each orbit of planet e, planet b completes two orbits and planet c completes four. This configuration is the second known example of a Laplace resonance after Jupiter's moons Io, Europa and Ganymede. Its orbit takes 124 days to complete.
Gliese 876 e has a mass similar to that of the planet Uranus. Its orbit takes 124 days to complete, or roughly one third of a year. While the orbital period is longer than that of Mercury around the Sun, the lower mass of the host star relative to the Sun means the planet's orbit has a slightly smaller semimajor axis. Unlike Mercury, Gliese 876 e has a nearly circular orbit with an eccentricity of 0.055 ± 0.012.
This planet, like b and c, has likely migrated inward.