Gliese 86 b

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Gliese 86 b
Extrasolar planet List of extrasolar planets
Gliese 86 Ab (Celestia).jpg
An artist's impression of Gliese 86 b.
Parent star
Star Gliese 86
Constellation Eridanus
Right ascension (α) 02h 10m 14s
Declination (δ) −50° 50′ 00″
Distance 35.9 ly
(11 pc)
Spectral type K1V
Orbital elements
Semimajor axis (a) 0.113[1] AU
Eccentricity (e) 0.0416 ± 0.0072[1]
Orbital period (P) 15.76491 ± 0.00039[1] d
Argument of
periastron
(ω) 269 ± 16[1]°
Time of periastron (T0) 2451903.36 ± 0.59[1] JD
Semi-amplitude (K) 376.7 ± 2.9[1] m/s
Physical characteristics
Mass (m) >3.91[1] MJ
Discovery information
Discovery date 24 November 1998[2]
Discoverer(s) Mayor et al.[3]
Discovery method Doppler spectroscopy
Discovery site  France
Discovery status Published
Other designations
Gl 86 (A)b, HD 13445 (A)b

Gliese 86 b, sometimes referred to as Gliese 86 Ab[citation needed] (so as to distinguish the planet from companion star "B") and or shortened to Gl 86 b, is an extrasolar planet approximately 36 light-years away in the constellation of Eridanus. The planet was discovered orbiting a K-type dwarf star (Gliese 86) by French scientists in November 1998.[2] The planet orbits very close to the star, completing an orbit in 15.78 days.

The preliminary astrometric measurements made with the Hipparcos space probe suggest the planet has an orbital inclination of 164.0° and a mass 15 times Jupiter, which would make the object a brown dwarf.[4] However, further analysis suggests the Hipparcos measurements are not precise enough to reliably determine astrometric orbits of substellar companions, thus the orbital inclination and true mass of the candidate planet remain unknown.[5]

The radial velocity measurements of Gliese 86 show a linear trend once the motion due to this planet are taken out. This may be associated with the orbital motion of the white dwarf companion star.

References[edit]

  1. ^ a b c d e f g Butler, R. et al. (2007). "Planets Table". Catalog of Nearby Exoplanets. Retrieved 2007-08-02. 
  2. ^ a b "Extrasolar Planet in Double Star System Discovered from La Silla" (Press release). Garching, Germany: European Southern Observatory. November 24, 1998. Retrieved December 29, 2012. 
  3. ^ Michel Mayor, Didier Queloz, Udry et al.
  4. ^ Han et al.; Black, David C.; Gatewood, George (2001). "Preliminary astrometric masses for proposed extrasolar planetary companions". The Astrophysical Journal Letters 548 (1): L57–L60. Bibcode:2001ApJ...548L..57H. doi:10.1086/318927. 
  5. ^ Pourbaix, D. and Arenou, F. (2001). "Screening the Hipparcos-based astrometric orbits of sub-stellar objects". Astronomy and Astrophysics 372 (3): 935–944. arXiv:astro-ph/0104412. Bibcode:2001A&A...372..935P. doi:10.1051/0004-6361:20010597. 

External links[edit]


Coordinates: Sky map 02h 10m 14s, −50° 50′ 00″