HAT-P-6b

HAT-P-6b / Nachtwacht
Size comparison of HAT-P-6b with Jupiter.
Discovery
Discovered byNoyes et al.
Discovery dateOctober 15, 2007
transit
Orbital characteristics
0.05239+0.00080
−0.00082
AU[1]
Eccentricity<0.044[1]
3.852985±0.000005[2] d
Inclination166±10 °[3]
StarHAT-P-6
Physical characteristics
1.33 ± 0.06 RJ[2]
Mass1.106+0.039
−0.040
[1] MJ
Mean density
0.583 g/cm3[1]

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]

Artist's impression of Hat-P-6b orbiting its host star with an aurora on its south pole.
  1. ^ a b c d e Cite error: The named reference Bonomo2017 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Noyes2008 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Hébrard2011 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Gaia was invoked but never defined (see the help page).
  5. ^ "Approved names". NameExoworlds. Retrieved 2020-01-02.
  6. ^ "International Astronomical Union | IAU". www.iau.org. Retrieved 2020-01-02.
  7. ^ Cite error: The named reference Todorov2012 was invoked but never defined (see the help page).