109 Piscium b

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109 Piscium b[1]
Extrasolar planet List of extrasolar planets
Orbital elements
Semimajor axis (a) 2.16±0.12 AU
Eccentricity (e) 0.1023±0.0096
Orbital period (P) 1076.4±2.4 d
Angular distance (θ) 65.418 mas
Longitude of
periastron		 (ω) 108.9±8.2°
Time of periastron (T0) 2,450,396±29 JD
Semi-amplitude (K) 115±1.5 m/s
Physical characteristics
Mass (m) >6.38±0.53 MJ
Discovery information
Discovery date November 14, 1999
Discoverer(s) Vogt et al.
Detection method Radial velocity
Discovery site Keck Observatory
Discovery status Published

109 Piscium b is a long-period extrasolar planet discovered in orbit around 109 Piscium. It is at least 6.38 times the mass of Jupiter and is likely to be a gas giant. As typical for long-period planets discovered around other stars, it has an orbital eccentricity greater than that of Jupiter.

The discoverers estimate its effective temperature as 264 K from solar heating, but it could be at least 10-20 K warmer because of internal heating[2] .

Preliminary astrometric measurements suggested that the orbital inclination is 170.3°[3], yielding an object mass of 38 times that of Jupiter, which would make it a brown dwarf. However, subsequent analysis indicates that the precision of the measurements used to derive the astrometric orbit is insufficient to constrain the parameters, so the true inclination and mass remain unknown.[4]

Planet Distance Insolation (W/m2)  % of Earth's
Mars' Aphelion Flux 494.00 36.06%
Mars' Average Flux 590.589 43.11%
Mars' Perihelion Flux 718.545 52.45%
109 Piscium b Apastron Flux 720.221 52.57%
109 Piscium b Average Flux 875.116 63.88%
109 Piscium b Periastron Flux 1085.933 [1] 79.27%
Earth's Aphelion Flux 1325.277 96.74%
Earth's Average Flux 1369.938 100.00%
Earth's Perihelion Flux 1416.896 103.43%

[1] fp=((((1.83 × 6.96e8)4)×(5.6704e-8)×(56144)) ÷ ((2.16-(2.16×0.1023))×149597876600)2


[edit] See also

[edit] References

  1. ^ Butler et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal 646 (1): 505 – 522. doi:10.1086/504701.  (web Preprint)
  2. ^ Vogt et al. (2000). "Six New Planets from the Keck Precision Velocity Survey". The Astrophysical Journal 536 (2): 902 – 914. doi:10.1086/308981. 
  3. ^ Han et al. (2001). "Preliminary astrometric masses for proposed extrasolar planetary companions". The Astrophysical Journal 548 (1): L57 – L60. doi:10.1086/318927. 
  4. ^ Pourbaix, D. and Arenou, F. (2001). "Screening the Hipparcos-based astrometric orbits of sub-stellar objects". Astronomy and Astrophysics 372: 935 – 944. doi:10.1051/0004-6361:20010597. 

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