NASA’s Artemis II rocket was expected to begin its rollout to the launch pad Thursday night, but the vehicle had not moved as scheduled, with weather conditions possibly contributing to the delay.

The United States is preparing to send astronauts around the Moon again after half a century, but the mission has faced repeated delays.

The massive system — topped with the Orion capsule, weighing more than 11 million pounds and taller than the Empire State Building — was rolled out overnight.