NASA’s Artemis II moon mission is on track to loop around our nearest satellite and back. On Thursday, around 7:50 P.M. EDT, the Orion spacecraft’s main engine, the European Service Module, ignited and jettisoned 6,700 pounds of monomethyl hydrazine propellant over the course of about six minutes. The “translunar injection burn” shoved the craft onto its correct path with 6,000 pounds of thrust—about the same amount needed to accelerate a car from zero to 60 miles an hour in 2.7 seconds—increasing its speed by 867 miles per hour.
“When the engine ignites, you embark on humanity’s lunar homecoming arc and set the course to return Integrity and her crew safely home,” said Houston Mission Control immediately before the burn. “Houston is go for TLI [translunar injection].”
“Integrity copies—and your Integrity crew is go for TLI,” replied astronaut Christina Koch. “With this burn to the moon, we do not leave Earth, we choose it.”
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Following the burn, the crew was “healthy,” and the Orion spacecraft was “performing really well,” said Lori Glaze, acting associate administrator for NASA’s Exploration Systems Development Mission Directorate, at a press conference on Thursday night. The burn was “flawless,” Glaze said. NASA isn’t tracking anything of concern at this point.
Ahead of the maneuver, the four-person crew—astronauts Reid Wiseman, Victor Glover, Christina Koch and Jeremy Hansen—performed a series of system checks to prepare. At the time of the burn, the spacecraft was just 115 miles above Earth.
Their work has put Artemis II hurtling toward the moon at a blistering speed of around 22,670 mph—the fastest it will go at any point in space. At the time of writing, the moon remains about 246,000 miles away; it will take Orion almost three days to enter the moon’s sphere of influence, where its gravitational pull on the craft will become stronger than Earth’s.
This trajectory will allow Orion to slingshot around the moon and back to Earth, meaning the return trip likely won’t need another large burn, and the spacecraft should splash down on April 10. There will be a couple of small planned fuel burns to stay on track over the next few days, however.
Now that this critical burn is complete, the crew will be more free to conduct experiments and possibly to speak to their families. “They’ve been really busy,” said NASA flight director Judd Frieling at the same press conference. “We’ll make time for that now that we’re past TLI.”
The Artemis II crew members will spend the rest of their journey to the moon testing life-support systems and rehearsing for when they’ll finally be over the lunar far side on Monday. On that day they will have a brief window to observe lunar features that have never been seen by human eyes and to take photographs and video. And on Monday they’re also poised to go farther than any human has ever traveled from Earth. Then, after their moon-assisted U-turn, the astronauts will begin the long trek home. The crew is scheduled to splash down in the Pacific Ocean at around 5:30 P.M. on April 10.
Additional reporting by Jackie Flynn Mogensen.