HAT-P-6b:: A hot jupiter transiting a bright F star

In the ongoing HATNet survey we have detected a giant planet, with radius 1.33 +/- 0.06 R(Jup) and mass 1.06 +/- 0.12 M(Jup), transiting the bright (V = 10.5) star GSC 03239-00992. The planet is in a circular orbit with period days and midtransit epoch 2,454,035.67575 +/- 0.00028 ( HJD). The parent star is 3.852985 +/- 0.000005 a late F star with mass, radius, 1.29 +/- 0.06 M(circle dot), radius 1.46 +/- 0.06 R(circle dot), T(eff) similar to 6570 +/- 80 K [Fe/H] = -0.13 +/- 0.08, and age similar to 2.3(-0.7)(+0.5) Gyr. With this radius and mass, HAT-P-6b has somewhat larger radius than theoretically expected. We describe the observations and their analysis to determine physical properties of the HAT- P- 6 system, and briefly discuss some implications of this finding.