HAT-P-20b orbits a V = 11.339 K3 dwarf star with a period P = 2.875317 +/- 0.000004d. The central star has a mass of 0.760 +/- 0.03 solar masses, radius of 0.690 +/- 0.02 Rsun, teff = 4595 +/- 80 K, and metallicity [Fe/H] = + 0.35 +/- 0.08. HAT-P-20b has a mass of 7.246 +/- 0.187 MJ, and the radius of 0.867 +/- 0.033 RJ producing an average density of 13.78 +/- 1.50 g cm^-3, which is the second highest value among all known exoplanets.
The parent star also harbors an M-dwarf companion in a wide separation.
https://arxiv.org/abs/1008.3388
Observations of HAT-P-20b
Collaborative projects
