Artemis II crew gets false leak warning before burn

On April 2, the Orion spacecraft, which had been completing a highly elliptical orbit around Earth to test its systems, reported a warning that a cabin leak might be occurring while it was only about 100 miles from the planet. The alert arrived 15 minutes before the translunar injection (TLI) burn that would send the crew toward the moon, and pilot Victor Glover recalled the crew and mission control had to decide whether to abort or proceed, saying the warning threatened to derail the mission.

TLI burn and trajectory

Mission control determined the leak warning was a false alarm, and the Orion's main engine fired for about five minutes and fifty seconds. The burn placed the four astronauts on a trajectory that would carry them around the moon, marking the first time astronauts had headed toward the moon since the Apollo era. Soon after, they were hurtling toward the moon at around 24,500 mph (39,430 kph), and they reached a maximum distance of 252,756 miles (406,771 km) from Earth.

As Orion passed around the far side of the moon, commander Reid Wiseman described feeling "real fear" as Earth appeared as a faint crescent. He called it the most terrifying moment of his trip around the moon.

The crew returned safely to Earth, splashing down in the Pacific Ocean off San Diego on April 10 after nearly 10 days in space, concluding the historic Artemis II flight.