4K Video: The launch of Crew 4 as seen from the press site

SpaceX kept an upgraded Falcon 9 rocket on the ground Thursday after running into a problem loading super-cold liquid propellants into the launcher’s fuel tanks, postponing blastoff of a commercial communications satellite for the second day in a row.

Astronauts Doug Hurley and Bob Behnken donned their SpaceX-made launch and entry flight suits Saturday and rode to pad 39A at the Kennedy Space Center in a final dress rehearsal before launch day.

Two days after launching a Falcon 9 rocket from Florida, SpaceX sent another mission into orbit Sunday from California’s Central Coast with 10 new satellites for Iridium’s voice and data relay network.