The Orion spacecraft fired its engines close to the moon Monday Nov. 21, finishing the maneuver successfully out of communication with Earth. The Artemis 1 mission's uncrewed capsule has been cruising toward the moon since launching Wednesday atop NASA's Space Launch System (SLS) rocket.
At its closest approach at 1244 UTC, Orion was around 80 miles above the lunar surface. Orion finished the burn by itself on the far side of the moon from our planet, where radio signals cannot penetrate from Earth. NASA was in the dark during this period.
Orion's "powered flyby burn," during the approach Monday, will help set its main engine on course to enter lunar orbit four days later.
According to NASA's Sandra Jones on Monday, the successful burn "sent Orion close enough to the lunar surface to leverage the moon's gravitational force, and swing the spacecraft once around the moon toward entry into a distant retrograde orbit."
Monday's burn will set up another crucial maneuver by Orion on Nov. 25: an engine firing designed to insert the spacecraft into a distant retrograde orbit (DRO) around the moon. It will stay in the DRO -- a stable path that will take it as far as 40,000 miles from the lunar surface — until Dec. 1, when another engine burn will send the spacecraft back toward Earth.
"This orbit is different than the orbit done during the Apollo program, in which the spacecraft and its crew orbited much closer to the lunar surface in a more circular fashion," Jones said. "Distant retrograde orbit is important because it helps us to learn about how a spacecraft functions in a deep space environment.
Artemis 1 mission is part of NASA's Artemis program of lunar exploration, which among other objectives, aims to set up a crewed research base on the moon within the next decade.
Orion spacecraft is set to break the record for the farthest distance traveled from Earth by any human-rated spacecraft, a record set during the Apollo era.
WATCH Orion's flyby above the lunar surface