It's one of those hitch hiking deals:
NASA's Deep Impact/EPOXI spacecraft will fly past Earth this Sunday (June 27). Mission navigators have tailored this trajectory so the spacecraft can "hitch a ride" on Earth's gravity field, which will help propel the mission toward its appointment with comet Hartley 2 this fall. At time of closest approach to Earth, the spacecraft will be about 30,400 kilometers (18,900 miles) above the South Atlantic.
"Earth is a great place to pick up orbital velocity," said Tim Larson, the EPOXI project manager from NASA's Jet Propulsion Laboratory in Pasadena, Calif. "This flyby will give our spacecraft a 1.5-kilometer-per-second [3,470 mph] boost, setting us up to get up close and personal with comet Hartley 2."
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This just in from NASA:
Nifty:
"You develop an instant global consciousness, a people orientation, an intense dissatisfaction with the state of the world, and a compulsion to do something about it. From out there on the Moon, international politics looks so petty.
Curiosity Rover is now tweeting its stuff. Things are going to get pretty exciting over the next few days as the space ship comes in for a landing on the Planet Mars.
Off-Topic: a recent article I found at HuffPo: "Is the Universe Merely a Statistical Accident?2
http://www.huffingtonpost.com/dr-larry-dossey/spiritual-living-is-the-u…