109 Piscium b

109 Piscium b (aka HD 10697 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.

109 Piscium b
Discovered byCalifornia and
Carnegie Planet Search
Discovery siteW. M. Keck Observatory
Discovery dateNovember 1, 1999
Doppler spectroscopy
Orbital characteristics[3]
2.140±0.088 AU
1,075.69±0.82 days
Star109 Piscium
Physical characteristics[3]
Mass≥6.383±0.078 MJ

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

Preliminary astrometric measurements suggested that the orbital inclination is 170.3°,[4] 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.[5]

A more plausible suggestion is that this planet shares its star's inclination, of 69+21

See alsoEdit


  1. ^ "Astronomers discover six new planets orbiting nearby stars" (Press release). Kamuela, Hawaii: W. M. Keck Observatory. November 1, 1999. Retrieved December 19, 2017.
  2. ^ a b Vogt, Steven S.; et al. (2000). "Six New Planets from the Keck Precision Velocity Survey". The Astrophysical Journal. 536 (2): 902–914. arXiv:astro-ph/9911506. Bibcode:2000ApJ...536..902V. doi:10.1086/308981.
  3. ^ a b Luhn, Jacob K.; et al. (2019). "Retired A Stars and Their Companions. VIII. 15 New Planetary Signals around Subgiants and Transit Parameters for California Planet Search Planets with Subgiant Hosts". The Astronomical Journal. 157 (4). 149. arXiv:1811.03043. Bibcode:2019AJ....157..149L. doi:10.3847/1538-3881/aaf5d0.
  4. ^ Han, Inwoo; 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.; 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.
  6. ^ "hd_10697_b". Extrasolar Planet Encyclopaedia. Retrieved November 12, 2012.
  7. ^ Roberto Sanchis-Ojeda; Josh N. Winn; Daniel C. Fabrycky (2012). "Starspots and spin-orbit alignment for Kepler cool host stars". Astronomische Nachrichten. 334 (1–2): 180–183. arXiv:1211.2002. Bibcode:2013AN....334..180S. doi:10.1002/asna.201211765.

Coordinates:   01h 44m 55s, +20° 04′ 59″