Live coverage: Atlas 5 countdown and launch journal

Working under the cloud of the global coronavirus pandemic, technicians and engineers at NASA’s Kennedy Space Center have installed a rotor-driven drone on the agency’s next Mars rover and fueled the spacecraft’s “sky crane” landing system in preparation for launch in July.

NASA awarded Northrop Grumman a contract worth as much as $84.5 million earlier this month to supply rocket motors for a first-of-its-kind launch vehicle to fire a capsule of rock samples off of Mars on a journey back to Earth.

SpaceX conducted a final Launch Readiness Review on Monday ahead of the scheduled liftoff Wednesday of NASA astronauts Doug Hurley and Bob Behnken on a test flight of the Crew Dragon spacecraft to the International Space Station. Launch remains set for 4:33:33 p.m. EDT (2033:33 GMT) Wednesday, weather permitting.