Powered by a Boeing Delta II 7925 launch vehicle, Phoenix will begin its mission within a 22 day launch window in August of 2007. The launch will take place at Cape Canaveral Air Force Station in Florida.
The Delta II 7925 was chosen due to its successful launch history. Several previous space exploration missions have launched on a Delta II 7925, including the Spirit and Opportunity Mars Rovers launched in 2003. The launch vehicle weighs 285,228 kilograms (628,820 pounds). Getting this weight off the ground is no easy feat. A Rocketdyne RS-27A engine is used in combination with nine strap-on rocket motors. The RS-27A is capable of producing 890,000 Newtons (200,000 pounds) of thrust. As stated on the Mars Exploration Rovers webpage, this amount of thrust is equivalent to the force generated by compressing water from 2,000 fire hoses into a single hose less than 1.5 meters (5 feet) in diameter.
After launch, Phoenix will perform various maneuvers to make the transition to the cruise stage. The spacecraft will deploy its solar arrays and re-orient itself in space. A connection to the NASA Deep Space Network will be initialized which will
Mars Pathfinder was launched aboard a Delta II 7925 in 1996. (Image credit: Florida Today, copyright 1996)