HD 196885 is a 6th magnitude binary star in the constellation Delphinus. According to its parallax of 29.15 milliarcseconds,[1] it is located at a distance of 112 light years from Earth. In 2004, a planet was announced to be orbiting the star in a 386-day orbit.[2] Follow-up work published in 2008 did not confirm the original candidate but instead found evidence of a planet in a 1349-day orbit.[3]
The star BD+10 4351B, located 192 arcseconds away from HD 196885 is located at the same distance and may be a physically-bound companion star, in which case HD 196885 is a triple system.[4] If it is bound, then the separation is at least 6600 AU (the separation along the line-of-sight is unknown, so this value represents a lower limit on the true separation).
HD 196885 A
HD 196885 A is an F6IV star. It has a mass of 1.33 solar masses and a radius of 1.79 times that of our Sun.[5]
Planetary system
The HD 196885 system
Companion
(in order from star) |
Mass |
Semimajor axis
(AU) |
Orbital period
(days) |
Eccentricity |
| b |
>2.96 MJ |
2.30 |
1349 |
0.462 |
HD 196885 B
HD 196885 B Observation data
Epoch 2000 Equinox 2000
Constellation Delphinus
Right ascension 20h 39m 51s
Declination +11° 14′ 58″
Distance 112 ly
(34.3 pc)
Spectral type M1V
HD 196885 B is a red dwarf star separated by 0.7 arcseconds from the primary star.[4] At a distance of 112 light years, this corresponds to a separation of 24 AU between the stars.[6] Since the separation along the line-of-sight is unknown, this represents a lower limit on the true separation.
See also
* Epsilon Reticuli
* GJ 3021
* List of extrasolar planets
References
1. ^ van Leeuwen, F. (2007). "HIP 101966". Hipparcos, the New Reduction. http://webviz.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=I/311/hip2&recno=101615. Retrieved 2008-08-19.
2. ^ "The Planet Around HD 196885". California & Carnegie Planet Search Team (Internet Archive link). http://web.archive.org/web/20041227061730/http://exoplanets.org/esp/hd196885/hd196885.shtml. Retrieved 2008-08-19.
3. ^ Correia, A. C. M.; Udry, S.; Mayor, M.; Eggenberger, A.; Naef, D.; Beuzit, J.-L.; Perrier, C.; Queloz, D.; Sivan, J.-P.; Pepe, F.; Santos, N. C.; Ségransan, D. (2008). "The ELODIE survey for northern extra-solar planets. IV. HD 196885, a close binary star with a 3.7-year planet". Astronomy and Astrophysics 479 (1): 271 – 275. doi:10.1051/0004-6361:20078908. http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2008A%26A...479..271C&db_key=AST&nosetcookie=1. Retrieved 2008-08-19.
4. ^ a b "HD 196885 A page". Geneva Observatory. http://obswww.unige.ch/exoplanets/hd196885A.html. Retrieved 2008-08-19.
5. ^ Schneider, J.. "Notes for star HD 196885". The Extrasolar Planets Encyclopaedia. http://exoplanet.eu/star.php?st=HD+196885. Retrieved 2008-08-19.
6. ^ Chauvin et al.; Lagrange, A.-M.; Udry, S.; Mayor, M. (2007). "Characterization of the long-period companions of the exoplanet host stars: HD 196885, HD 1237 and HD 27442" (abstract). Astronomy and Astrophysics 475 (2): 723–727. doi:10.1051/0004-6361:20067046. http://www.aanda.org/articles/aa/abs/2007/44/aa7046-06/aa7046-06.html. (web preprint)
External links
* "HD 196885". Extrasolar Visions. http://www.extrasolar.net/planettour.asp?StarCatId=normal&StarId=262.
