NASA Begins Countdown Rehearsal for First Crewed Moon Mission in 50 Years

NASA on Saturday began a two-day practice countdown for its new moon rocket, a key test ahead of fueling that will determine when four astronauts can launch on a lunar flyby mission.

Already in quarantine to avoid illness, commander Reid Wiseman and his crew will monitor the rehearsal from Houston before traveling to Kennedy Space Center once the rocket is cleared for flight. They are set to become the first humans to journey toward the moon since 1972.

The 322-foot (98-meter) Space Launch System rocket was rolled out to the launch pad two weeks ago. If Monday’s fueling test proceeds smoothly, NASA could attempt a launch within a week. The test will involve pumping more than 700,000 gallons of super-cold propellant into the rocket’s tanks, stopping just seconds before engine ignition.

A severe cold spell delayed the demonstration and launch schedule by two days, pushing the earliest possible liftoff to February 8.

The US and Canadian astronauts will ride in the Orion capsule atop the rocket, looping around the moon before returning directly to Earth for a Pacific Ocean splashdown. The mission is expected to last nearly 10 days.

Between 1968 and 1972, NASA’s Apollo program sent 24 astronauts to the moon, with 12 walking on its surface.