WASP-12b: A Mass-Losing Extremely Hot Jupiter

摘要: WASP-12b is an extreme hot Jupiter in a 1 day orbit, suffering profound irradiation from its F type host star. The planet surrounded by translucent exosphere which overfills the Roche lobe and produces line-blanketing absorption near-UV. losing mass. Another unusual property of WASP-12 system that observed chromospheric emission star anomalously low: outlier amongst thousands stars when log $R^{'}_{HK}$ activity indicator considered. Occam's razor suggests these two extremely rare properties coincide this because they are causally related. absence expected attributable to diffuse circumstellar gas shroud surrounds entire planetary fills our line sight chromospherically active regions This probably fed mass loss WASP-12b. orbital eccentricity small but may be non-zero. part hierarchical quadruple system; current orbit consistent with prior secular dynamical evolution leading highly eccentric followed tidal circularization. When compared Galaxy's population planets, lies on upper boundary sub-Jovian desert both $(M_{\rm P}, P)$ $(R_{\rm planes. Determining rate for will illuminate mechanism(s) responsible desert.