NASA's Artemis 1 Orion capsule will perform a crucial engine burn during a flyby of the moon on Monday morning (Dec. 5), and you can follow the action live.
The uncrewed Orion is scheduled to perform a 207-second engine burn — its longest of the Artemis 1 mission — Monday at 11:43 a.m. EST (1643 GMT), when it's just 79 miles (128 kilometers) above the lunar surface.
NASA will cover the maneuver live, beginning at 9 a.m. EST (1400 GMT). Watch it live here at Space.com or directly via the space agency.
Artemis 1 is a shakeout cruise for Orion and NASA's Space Launch System (SLS) rocket, which launched the capsule on Nov. 16. If all goes well with the mission, the duo will launch astronauts around the moon on Artemis 2 in 2024 and help put boots down near the lunar south pole a year or so later on Artemis 3.
These missions are part of a broader effort to set up a crewed moon base by the end of the decade — one of the major goals of NASA's Artemis program.
SLS did its job nicely during Artemis 1's launch, and Orion has been performing up to expectations on the mission as well, NASA officials have said.
The capsule arrived in lunar orbit as planned on Nov. 25 and departed on schedule on Dec. 1, thanks to a 105-second engine firing. But the spacecraft still has some big boxes left to check, starting with Monday's engine burn.
The "powered return flyby" burn will put Orion on track to return to Earth on Dec. 11. On that day, the capsule will barrel into Earth's atmosphere at nearly 25,000 mph (40,000 kph), giving its heat shield a serious stress test. The structure will experience temperatures of about 5,000 degrees Fahrenheit (2,800 Celsius) — half as hot as the surface of the sun.
If the heat shield and Orion's parachutes do their jobs on Dec. 11, the capsule will splash down in the Pacific Ocean off the coast of California, bringing an end to the Artemis 1 mission.