HAT-P-6b is a transiting extrasolar planet discovered by Noyes et al. on October 15, 2007.[2] It is located approximately 910 light-years away[4] in the constellation of Andromeda, orbiting the star HAT-P-6. This hot Jupiter planet orbits with a semi-major axis of about 0.05 AU, and takes 92 hours, 28 minutes, 17 seconds to orbit the star.[2] It has true mass of 5.7% greater than Jupiter and a radius 33% greater than Jupiter, corresponding to a density of 0.583 g/cm3, which is less than water.[1]
The planet HAT-P-6b is named Nachtwacht. The name was selected in the NameExoWorlds campaign by the Netherlands, during the 100th anniversary of the IAU, after Rembrandt's painting The Night Watch.[5][6]
The sky projected angle between stellar and orbital axis is roughly 166°, making it one of the few planets that is in a retrograde orbit around its parent star.[3] Observations made by Spitzer Space Telescope shows that the planet atmosphere has a weak temperature inversion, or no inversion at all, depending on how strong is the stellar chromospheric activity.[7]
References
^ abcdeBonomo, A. S.; et al. (2017). "The GAPS Programme with HARPS-N at TNG . XIV. Investigating giant planet migration history via improved eccentricity and mass determination for 231 transiting planets". Astronomy and Astrophysics. 602. A107. arXiv:1704.00373. Bibcode:2017A&A...602A.107B. doi:10.1051/0004-6361/201629882. S2CID 118923163.
^ abcdNoyes, R. W.; et al. (2008). "HAT-P-6b: A Hot Jupiter Transiting a Bright F Star". The Astrophysical Journal Letters. 673 (1): L79–L82. arXiv:0710.2894. Bibcode:2008ApJ...673L..79N. doi:10.1086/527358. S2CID 2301387.
^Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.