Watch a replay of the Delta 4 NROL-47 launch

SpaceX technicians at Cape Canaveral are readying for the first launch of an upgraded Falcon 9 rocket configuration next week, a mission that will debut changes to make the launcher safer for astronauts and make it easier — and less expensive — for the company to reuse first stage boosters.

The four astronauts preparing to ride SpaceX’s Crew Dragon “Resilience” into orbit climbed aboard their spaceship Thursday at the Kennedy Space Center in a practice run for a launch to the International Space Station planned Saturday night, while mission managers monitored weather and sea conditions in recovery areas across the Atlantic Ocean.

The United Launch Alliance Atlas 5 rocket carrying NASA’s InSight lander toward Mars will have a roughly two-hour predawn launch window each day from May 5 through June 8 to boost the science probe into space from Vandenberg Air Force Base, California.