* Astronomy

Title: WASP-78b and WASP-79b: Two highly-bloated hot Jupiter-mass exoplanets orbiting F-type stars in Eridanus
Authors: B. Smalley (Keele University), D.R. Anderson, A. Collier-Cameron, A.P. Doyle, M. Gillon, C. Hellier, E. Jehin, M. Lendl, P.F.L. Maxted, F. Pepe, D. Pollacco, D. Queloz, D. Segransan, A.M.S. Smith, J. Southworth, A.H.M.J. Triaud, S. Udry, R.G. West

We report the discovery of WASP-78b and WASP-79b, two highly-bloated Jupiter-mass exoplanets orbiting F-type host stars. WASP-78b orbits its V=12.0 host star (TYC 5889-271-1) every 2.175 days and WASP-79b orbits its V=10.1 host star (CD-30 1812) every 3.662 days. A simultaneous fit to WASP and TRAPPIST transit photometry and CORALIE radial-velocity measurements yields planetary masses of 0.89 ±0.08 Jupiter masses and 0.90 ±0.08 Jupiter masses, and radii of 1.70 ±0.11 Jupiter radii and 2.09 ±0.14 Jupiter radii, for WASP-78b and WASP-79b, respectively. The planetary equilibrium temperature of T_P = 2350 ±80 K for WASP-78b makes it one of the hottest of the currently known exoplanets. The radius of WASP-79b suggests that it is potentially the largest known exoplanet.

Read more (75kb, PDF)