HAT-P-5b:: a jupiter-like hot jupiter transiting a bright star

We report the discovery of a planet transiting a moderately bright (V=12.00) G star, with an orbital period of 2.788491 +/- 0.000025 days. From the transit light curve we determine that the radius of the planet is R(P)=1.257 +/- 0.053 R(J). HAT-P-5b has a mass of M(P)=1.06 +/- 0.11 M(J), similar to the average mass of previously known transiting exoplanets, and a density of rho(P)=0.66 +/- 0.11 g cm(-3). We find that the center of transit is T(c)=2,454,241.77663 +/- 0.00022 days (HJD), and the total transit duration is 0.1217 +/- 0.0012 days.