Gliese 876 e

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Exoplanet
Gliese 876 e

Artist's impression of Gliese 876 e

Artist's impression of Gliese 876 e
Constellation Aquarius
Position
equinox : J2000.0
Right ascension 22h 53m 16.73352s
declination −14 ° 15 ′ 49.3186 ″
Orbit data
Central star Peter 876
Major semi-axis 0.345   + 0.001−0.002 AE
eccentricity 0.040   +0.021−0.004
Period of circulation 124.4   +0.3−0.7 d
Further data
Minimum dimensions 15.43   +1.29−1.27 M ♁
distance 4.660 ± 0.004 pc
history
discovery Rivera et al.
Date of discovery 2010
Catalog names
GJ 876 e, IL Aqr e, HIP 113020 e

Gliese 876 e is a Exoplanet which the 15 light-years from the sun away red dwarf Gliese 876 in the constellation Aquarius orbits. It is the outermost known planet in the star's planetary system .

discovery

Like the three previously discovered planets Gliese 876 b , Gliese 876 c and Gliese 876 d , Gliese 876 e was also discovered using the radial velocity method. The discovery was announced in 2010 by a team of astronomers led by Eugenio Rivera (who had already discovered Gliese 876 d in 2005) on the basis of continued measurements with the Échelle spectrograph HIRES at the Keck Observatory .

properties

Gliese 876 e orbits its central star at a distance of about 0.45 AU in just over 124 days. Its minimum mass is around 14.6 Earth masses or around 0.046 masses of Jupiter and thus roughly corresponds to that of the planet Uranus in the solar system. It is in a Laplace resonance with its inner neighboring planets Gliese 876 b and Gliese 876 c : on four orbits of Gliese 876 c there are two of Gliese 876 b and one of Gliese 876 e. The three planets are comparable to the three Jupiter moons Io , Europa and Ganymede , which are also in a Laplace resonance.

Like its two inner neighboring planets, Gliese 876 e was formed, presumably at a greater distance from the star, before it reached its current orbit like them through migration . The planet's orbital inclination is likely 59 °.

Individual evidence

  1. ↑ SIMBAD: Gliese 876. Retrieved July 5, 2015 .
  2. ↑ a b c d T. Trifonov et al .: The CARMENES search for exoplanets around M dwarfs. First visual-channel radial-velocity measurements and orbital parameter updates of seven M-dwarf planetary systems. (PDF) October 4, 2017, p. 17 , accessed on January 18, 2018 . doi : 10.1051 / 0004-6361 / 201731442 , arxiv : 1710.01595
  3. ↑ a b c Eugenio J. Rivera et al .: The Lick-Carnegie Exoplanet Survey: A Uranus-mass Fourth Planet for GJ 876 in an Extrasolar Laplace Configuration . arxiv : 1006.4244 .
  4. ↑ Gerlach, E .; Haghighipour, N .: Can GJ 876 host four planets in resonance? arxiv : 1202.5865 .