A close-up view of NASA's Artemis 1 Space Launch System megarocket inside the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on Sept. 20, 2021.

A close-up view of NASA's Artemis 1 Space Launch System megarocket inside the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on Sept. 20, 2021. (Image credit: NASA/Frank Michaux)

The Artemis 1 moon mission may end up being a summertime affair.

An April launch is no longer possible for Artemis 1, which will send an uncrewed Orion spacecraft around the moon using a huge Space Launch System megarocket, agency officials said today. It could be difficult to hit in May.

"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 today during a virtual news conference.

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Some of that work will involve analyzing data from the Artemis 1 wet dress rehearsal, a crucial test that will take the SLS-Orion stack through many of the milestones it will hit on launch day.

The dress rehearsal will take place on Pad 39B at the Kennedy Space Center in Florida. The SLS and Orion will roll out to the pad from the cavernous Vehicle Assembly Building at 6 p.m. Agency officials said on March 17 It will take about 12 hours for the huge vehicle to travel to the pad.

The SLS-Orion stack will probably be on Pad 39B for about a month and on either side of the wet dress rehearsal for about two weeks. The vehicle will return to the VAB for further analysis.

The May launch window runs from the 7th to the 21st. The next opportunity will be from June 6 through June 16 if Artemis 1 isn't ready to go by then. The next window is from June 29 to July 12.

The windows are limited for a number of reasons. He said that the SLS needs to line the launch up with the Earth's rotation and the position of the moon in order to perform well.

NASA is taking its time to make sure that everything is in order before the launch of Artemis 1, a huge mission for the agency and its Artemis program of crewed lunar exploration. The first flight of the huge and powerful SLS and the second mission for Orion will be marked by Artemis 1, which will be the first flight of the huge and powerful SLS.

If all goes well during the 26 days of Artemis 1, NASA will start preparing for Artemis 2, which will send astronauts on a journey around the moon. The first crewed mission for NASA since the Apollo era is scheduled to take place in 2024. If all goes according to plan, Artemis 3 will put astronauts on the moon in the year 2025.

The lunar touchdown is not the Artemis endpoint. The goal of the program is to establish a long-term, sustainable human presence on and around the moon. The lessons and skills gained from doing that will help NASA put astronauts on Mars.

Mike Wall is the author of Out There, a book about the search for alien life. You can follow him on social media. Follow us on social media.