Watch a time-lapse of the Falcon 9 rocket going vertical

A Falcon 9 rocket is again standing upright on launch pad 39A at NASA’s Kennedy Space Center in Florida after ground teams lowered the booster Friday to swap out mice heading to the International Space Station for medical experiments.

SpaceX’s Falcon 9 booster is set for liftoff from Cape Canaveral on Sunday morning, but most of the launcher’s ascent into orbit will be under a news blackout at the request of the National Reconnaissance Office, the secretive U.S. government intelligence agency whose mission is riding on the rocket.

SpaceX’s launch team ran through a traditional preflight test Monday, putting a Falcon 9 rocket through a mock countdown, loading it with propellant and briefly firing its nine engines on a launch pad in California ahead of this weekend’s liftoff with a U.S.-European oceanography satellite.