NASA is planning to launch four astronauts around the moon as soon as April 1, it said on Thursday.
The setting of the timeline for Artemis II, a mission that will send astronauts near the moon for the first time in more than half a century, came as the agency completed a review of efforts to address technical issues that resulted in postponements of launch attempts in February and March.
“It’s a test flight, and it is not without risk, but our team and our hardware are ready,” said Lori Glaze, the acting associate administrator for NASA’s Exploration Systems Development Mission Directorate. Pending completion of the remaining work required to prepare for flight, she said, “we are on track for a launch as early as April 1. And we are working toward that date.”
Artemis II is expected to loop a crew of four astronauts around the far side of the moon without landing on the lunar surface and bring them back to Earth on a mission that will take about 10 days. Like its predecessor, Artemis I, the mission will lift off on a giant rocket called the Space Launch System. Future NASA missions, currently planned for 2028, will attempt to return astronauts to the moon’s surface.
The four astronauts on the mission are Reid Wiseman, the mission’s commander; Victor Glover, its pilot; and two mission specialists, Christina Koch and Jeremy Hansen. Mr. Glover would be the first Black man to travel around the moon, and Ms. Koch the first woman, while Mr. Hansen, a Canadian Space Agency astronaut, would be the first astronaut to make the trip who is not a U.S. citizen.
The four will enter a period of quarantine ahead of their flight on March 18.
NASA rolled the rocket and Orion, the capsule in which the crew is to travel, to the launchpad in January ahead of a scheduled flight attempt in early February. But Artemis II was delayed by a month because of a hydrogen leak that occurred during a dress rehearsal in which the mission team filled the fuel tanks of the rocket to assess any issues before flight.
The agency then completed a successful dress rehearsal later in February. But mission specialists identified an interruption in the flow of helium to the upper stage of the rocket. Helium is used to pressurize the liquid hydrogen and oxygen that are used as propellants for the rocket engine. As a result, NASA rolled the rocket and the capsule away from the launchpad and into a giant hangar called the Vehicle Assembly Building for repairs.
According to Shawn Quinn, the manager of NASA’s Exploration Ground Systems Program, engineers identified a seal that was blocking the flow of helium to the rocket and tweaked its design.
Fixing the issue made it possible to schedule the launch of Artemis II for April.
Originally, the launch could only have been scheduled for April 1, 3, 4, 5 or 6. But Dr. Glaze said further analysis allowed the mission team to add April 2 to the launch window, for a total of six possible flight days.
NASA is aiming to roll the rocket back to the launchpad by March 19. According to Mr. Quinn, a few more tasks need to be completed in the Vehicle Assembly Building before rollout, including the removal of platforms surrounding the rocket and various checkout procedures.
“That’s pretty much it,” Mr. Quinn said. “We’re close.”
The mission team said on Thursday that another countdown dress rehearsal in which the rocket would be fueled was not needed before an April launch attempt.
“Every time we tank the vehicle, it takes a bit of the life out of those tanks,” Dr. Glaze said. If the vehicle can be successfully fueled, she added, “I want to be able to pull ‘go’ to launch. So that’s where we are at this point.”
The NASA officials declined to discuss any dates for launch attempts beyond April should another issue thwart the latest window.
“Yes, there are opportunities in other months,” Dr. Glaze said, “but right now, we are solely focused on April.”
