In addition to carrying an Air Force electric propulsion thruster test, a materials research investigation sponsored by NASA’s Marshall Space Flight Center will be flying aboard the X-37B miniature spaceplane later this month.

Two U.S. Air Force cargo planes delivered the Mars 2020 rover, cruise stage, descent module and the Mars Helicopter to the Kennedy Space Center in Florida this week for final assembly, fueling and mounting atop a United Launch Alliance Atlas 5 rocket in preparation for liftoff in July.

The most powerful variants of the Atlas 5 and Delta 4 rockets have been purchased by the Air Force to launch intelligence-gathering spacecraft for the U.S. government, and NASA has bought an Atlas 5 to deploy a critical polar-orbiting weather satellite.