CAPE CANAVERAL, Fla. - In the Space Shuttle Main Engine Processing Facility at NASA's Kennedy Space Center in Florida, a main engine is secured to a transporter and ready for its move to Orbiter Processing Facility Bay 3. There, it will be installed in space shuttle Discovery during processing for the shuttle's STS-131 mission to the International Space Station.The seven-member STS-131 crew will deliver a Multi-Purpose Logistics Module filled with resupply stowage platforms and racks to be transferred to locations around the station. Three spacewalks will include work to attach a spare ammonia tank assembly to the station's exterior and return a European experiment from outside the station's Columbus module. Discovery's launch, targeted for March 18, 2010, will initiate the 33rd shuttle mission to the station.