Comet Hits Jupiter

Several years ago several chunks of a comet slammed into the far side of Jupiter. Given that $M_{\rm Jupiter} = 1.9\times10^{27}$ kg and $R_{\rm Jupiter} = 7\times10^4$ km, estimate how much energy was released in the (inelastic) collisions of a typical comet fragment with Jupiter. Assume that the comet fragment is a ball of ice with density $\approx 1$ gm/cm$^3$ and of radius 0.5 km. State clearly the basis of your argument, drawing pictures or graphs if necessary.