Gliese 876 e

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Gliese 876 e
Extrasolar planet List of extrasolar planets
ConceptJKV-Gliese876-e.png
Artist's concept of Gliese 876 e
Parent star
Star Gliese 876
Constellation Aquarius
Right ascension (α) 22h 53m 16.73s
Declination (δ) −14° 15′ 49.3″
Apparent magnitude (mV) 10.17
Distance 15.3 ly
(4.72 pc)
Spectral type M4V
Mass (m) 0.334 ± 0.030 M
Radius (r) 0.36 R
Temperature (T) 3350 ± 300 K
Metallicity [Fe/H] 0.05 ± 0.20
Age 0.1–5.0 Gyr
Orbital elements
Epoch HJD 2,450,602.093
Semimajor axis (a) 0.3343 ± 0.0013 [1] AU
Eccentricity (e) 0.055 ± 0.012 [1]
Orbital period (P) 124.26 ± 0.70 [1] d
Inclination (i) 59.5 [1]°
Argument of
periastron
(ω) 239 ± 22 [1]°
Mean anomaly (M) 335 ± 24 [1]°
Semi-amplitude (K) 3.42 ± 0.39 [1] m/s
Physical characteristics
Mass (m) 14.6 ± 1.7 [1] M
Discovery information
Discovery date June 23, 2010
Discoverer(s) Rivera et al.
Discovery method Doppler spectroscopy
Discovery status published [1]
Database references
Extrasolar Planets
Encyclopaedia
data
SIMBAD data
The orbits of the planets of Gliese 876. Gliese 876 e is the furthest planet from the star.

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.[1]

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.[1]

This planet, like b and c, has likely migrated inward.[2]

References[edit]

  1. ^ a b c d e f g h i j k Rivera, Eugenio J. et al. (July 2010). "The Lick-Carnegie Exoplanet Survey: A Uranus-mass Fourth Planet for GJ 876 in an Extrasolar Laplace Configuration". The Astrophysical Journal 719 (1): 890–899. arXiv:1006.4244. Bibcode:2010ApJ...719..890R. doi:10.1088/0004-637X/719/1/890. 
  2. ^ Gerlach, Enrico; Haghighipour, Nader (2012). "Can GJ 876 host four planets in resonance?". arXiv:1202.5865. Bibcode:2012CeMDA.113...35G. doi:10.1007/s10569-012-9408-0.