HD 33636 is a binary system located approximately 94 light-years away in Orion constellation. The visible member HD 33636 A is a 7th magnitude yellow main-sequence star. It is located at a distance of 93.6 light years from our home planet. It has Fe/H of −0.05 +/- 0.07.
A companion was discovered in 2003 with a minimum mass of planet size. This was ascertained to be a tiny star in 2007, making it HD 33636 B.
HD 33636 B
HD 33636 B was discovered in 2003 by Perrier et al. who used ELODIE spectrometer in France. With this method it showed a minimum mass of 9.28 Jupiter masses, and was initially assumed to be a planet and provisionally labelled "HD 33636 b" (lower-case).
In 2007, Bean et al. used the Hubble Space Telescope (HST) and he found that this body has an inclination as little as 4.1 ± 0.1°, which yielded the true mass of 142 Jupiter masses. This is too high to be a planet. It is now classified as an M-dwarf star of spectral type M6V, "HD 33636 B" (upper-case).
This star takes 2117 days or 5.797 years to orbit at the average distance of 3.27 Astronomical Units (AU).
1. ^ a b Perrier et al.; Sivan, J.-P.; Naef, D.; Beuzit, J. L.; Mayor, M.; Queloz, D.; Udry, S. (2003). "The ELODIE survey for northern extra-solar planets. I. Six new extra-solar planet candidates". Astronomy and Astrophysics 410: 1039–1049. doi:10.1051/0004-6361:20031340. http://adsabs.harvard.edu/abs/2003A%26A...410.1039P. Retrieved December 21, 2007.
* Butler et al.; Wright, J. T.; Marcy, G. W.; Fischer, D. A.; Vogt, S. S.; Tinney, C. G.; Jones, H. R. A.; Carter, B. D. et al. (2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal 646 (1): 505–522. doi:10.1086/504701. http://www.iop.org/EJ/article/0004-637X/646/1/505/64046.html.
* "HD 33636 -- Yellow Main Sequence Star". Extrasolar Visions. http://www.extrasolar.net/startour.asp?StarCatId=normal&StarId=150. Retrieved December 21, 2007.