The launch of NASA's Artemis 1 lunar mission has been postponed.

Artemis 1, which would send an uncrewed Orion spacecraft around the moon using a massive Space Launch System (SLS) megarocket, will no longer launch in April, according to Thursday's announcement by agency officials. May could also be tough to hit.

"We continue to evaluate the May window, but we're also recognizing that there's a lot of work in front of us," Tom Whitmeyer, deputy associate administrator for exploration systems development at NASA headquarters in Washington, said during a virtual news conference.

Some of that work will entail reviewing data from the Artemis 1 "wet dress rehearsal," an important test that will put the SLS-Orion stack through many of the milestones it will face on launch day.

The wet dress rehearsal, like the launch, will take place on Pad 39B at NASA's Kennedy Space Center (KSC) in Florida. SLS and Orion are planned to roll out to the pad at 6 p.m. from KSC's massive Vehicle Assembly Building (VAB). Officials from the agency said today that the event will take place in Mar. 17 at 2:00 p.m. EST. The massive vehicle will most likely take roughly 12 hours to make the comparatively short journey to the pad.

According to agency officials, the SLS-Orion stack will likely spend about a month on Pad 39B, with roughly two weeks on either side of the wet dress rehearsal. After that, the vehicle will return to the VAB for more analysis and processing.

Whitmeyer stated the launch window in May stretches from May 7 to May 21. If Artemis 1 isn't ready by then, the next chance will be from June 6 to June 16. After that, the next window runs from June 29 through July 12.

If everything goes well during Artemis 1's estimated 26-day mission, NASA will begin planning for Artemis 2, which will carry men on a tour around the moon. NASA's first crewed mission beyond Earth orbit since the Apollo period is tentatively scheduled for 2024. If all goes as planned, Artemis 3 will land astronauts on the moon in 2025 or so, utilizing a SpaceX Starship vehicle.

And the Artemis endpoint isn't a lunar touchdown. The program's goal is to create a long-term, sustainable human presence on and around the moon. The experiences and abilities learned will help NASA's next big leap - sending astronauts to Mars, which the agency hopes to undertake in the 2030s.