Gliese 317

Gliese 317
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pyxis
Right ascension 08h 40m 59.21s
Declination –23° 27′ 22.6″
Apparent magnitude (V) 12.0
Distance 49.9 ly
(15.3 pc)
Spectral type M3.5V
Other designations
GJ 317, LFT 538, LHS 2037, LPM 296, LTT 3215
Database references
SIMBAD data

Gliese 317 is a red dwarf star approximately 50 light-years away in the constellation of Pyxis. The star has an apparent magnitude of 12, an absolute magnitude of 12.2, and corresponding to visual luminosity of 0.1% Sun. As of 2007, at least one extrasolar planet has been confirmed to be orbiting the star.

Contents

Planetary system

Announced in 2007, a jovian planet (designated Gliese 317 b) was confirmed to orbit the star.[1] The planet orbits about 95% the distance between Earth to the Sun. Despite of this, it takes about 1.9 years, corresponding to slow orbital velocity of 14.82 km/s.

There is a possible second planet in the system; if it exists, the orbital parameters would change for the first planet. It would have an orbital period of 673.4 days and eccentricity of 0.25. A stability analysis on this putative system constrained its orbits to a 4:1 mean motion resonance.[2]

The Gliese 317 system[1]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity
b >1.2 MJ 0.95 692.9 ± 4 0.193 ± 0.06
c (unconfirmed) 0.83 MJ ~2.4[3] ~2700 ~0.42

See also

References

  1. ^ a b Johnson et al. (2007). "A New Planet Around an M Dwarf: Revealing a Correlation Between Exoplanets and Stellar Mass". The Astrophysical Journal 670 (1): 833–840. Bibcode 2007ApJ...670..833J. doi:10.1086/521720. http://www.iop.org/EJ/article/0004-637X/670/1/833/72377.html. 
  2. ^ Rory Barnes; Richard Greenberg (2008). "Extrasolar Planet Interactions". arXiv:0801.3226v1 [astro-ph]. 
  3. ^ Calculated using Kepler's third law for a star mass of 0.24 solar masses and a period of 2700 days.

External links


Coordinates: 08h 40m 59.21s, −23° 27′ 22.6″