by Anthony Ayiomamitis
The light curve for exoplanet HAT-P-12b in Canis Venatici depicted above is one of the latest transitting exoplanets, having being announced in Apr/2009, and represents the twelveth discovery by the Hungarian-based HATNet Project team. HAT-P-12b is characterized with a mass 0.211 times that of Jupiter while its radius is equivalent to 0.959 Jupiter radii, thus making this exoplanet the least dense gas-dominated exoplanet found to-date and which is more characteristic of a "hot Saturn". HAT-P-12b requires 140 minutes to transit its parent star at a depth of 25 mmag or 2.5%. The parent star, GSC 3033:706, is an K4 dwarf estimated to have a mass of 0.73 solar masses, a radius equivalent to 0.70 solar radii, a temperature of 4,650° K and to lie at a distance of 465 light-years away with a visual magnitude of 12.84. The C- and K-stars used for the purposes of the differential photometry measurements depicted above were GSC 3033:765 (mag 12.6) and GSC 3033:875 (mag 12.7) respectively.
Location: Athens, Greece (38.2997° N, 23.7430° E)
Date: May 13-14, 2009 23:05:02 - 03:10:03 UT+3
Equipment: AP 160 f/7.5 Starfire EDF, AP 1200GTO GEM, SBIG ST-10XME, SBIG CFW-10, Astrodon Tru-Bal LRGB
Integrations: Lum: 152 x 90 sec, Dark: 15 x 90 sec, Flat: ~17,750 ADU, Binning: 2x2
Further details regarding HAT-P-12 and HAT-P-12b including the paper published by the discovery team led by J.D. Hartman et al, see http://www.perseus.gr/Astro-Photometry-HAT-P-12-20090513.htm .