English: At NASA's Kennedy Space Center in Florida, workers accompany space shuttle Discovery as it is moved from Orbiter Processing Facility-3 to the Vehicle Assembly Building, or VAB. In the VAB, Discovery will be lifted into a high bay where it will be mated to its external tank and solid rocket boosters. The seven-member STS-131 crew will deliver the Multi-Purpose Logistics Module Leonardo, filled with resupply stowage platforms and racks, to the International Space Station aboard space shuttle Discovery. 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 will be conducted during three spacewalks. STS-131, targeted for launch on April 5, will be the 33rd shuttle mission to the station and the 131st shuttle mission overall