
Well, yeah, but..
"Earth is a great place to pick up orbital velocity," said Tim Larson, the EPOXI project manager from NASA's Jet Propulsion Laboratory. "This flyby will [get us] up close and personal with comet Hartley 2."
Oh, sure, really handy for you space-boffins and your probes! Send the Earth spiraling into the Sun just to visit a comet. The nerve!