NASA is set to launch Artemis II at 6:24 p.m. ET from Kennedy Space Center, marking a historic return to deep space with astronauts aboard for the first time in more than 50 years.

Four astronauts are on board the flight, which is the first crewed moon mission since 1972.

The successful translunar injection burn took the Orion spacecraft out of Earth’s orbit, propelling the craft on a four-day outbound trip to the Moon.