109 Piscium b

109 Piscium b

Render of 109 Piscium b made with SpaceEngine
Discovery[1][2]
Discovered by	California and Carnegie Planet Search
Discovery site	W. M. Keck Observatory
Discovery date	November 1, 1999
Detection method	Doppler spectroscopy
Orbital characteristics[3]
Semi-major axis	2.051+0.079 −0.087 AU
Eccentricity	0.104+0.009 −0.008
Orbital period (sidereal)	2.944 ± 0.002 years (1,075.30 ± 0.73 d)
Inclination	86.116°+19.957° −20.530°
Longitude of ascending node	38.852°+15.084° −21.589°
Time of perihelion	2,449,333.898+14.739 −15.380
Argument of perihelion	112.816°+5.254° −5.448°
Semi-amplitude	114.583+1.067 −1.196 m/s
Star	109 Piscium
Physical characteristics[3]
Mean radius	1.152 RJ[4]
Mass	5.743+1.011 −0.289 MJ

109 Piscium b (aka HD 10697 b) is a long-period extrasolar planet discovered in orbit around 109 Piscium. It is about 5.74 times the mass of Jupiter and is likely to be a gas giant. As is common 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 to 20 K warmer because of internal heating.[2] It orbits within the habitable zone.[1]

Preliminary astrometric measurements suggested that the orbital inclination is 170.3°,[5] 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.[6] A more plausible suggestion is that this planet shares its star's inclination, of 69^+21
₋₂₆°.[7][8] In 2022, the inclination and true mass of 109 Piscium b were measured via astrometry. The inclination estimate is consistent with that of the stellar rotation.[3]

See also

• 54 Piscium b – another nearby planet in the constellation of Pisces
• List of exoplanets discovered before 2000

References

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. 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. Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.
4. "The Extrasolar Planet Encyclopaedia — 109 Psc b". Extrasolar Planets Encyclopaedia. Paris Observatory.
5. 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. S2CID 120952927.
6. 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.
7. "hd_10697_b". Extrasolar Planets Encyclopaedia. 1995. Retrieved November 12, 2012.
8. 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. S2CID 38743202.