NASA's Artemis 1 moon mission won't wrap up a crucial test until this weekend at the earliest.
Artemis 1 will use a huge Space Launch System (SLS) rocket to send an uncrewed Orion spacecraft on a roughly month-long mission around the moon. Artemis 1 is expected to lift off in June or thereabouts, but NASA won't set a target date until it finishes a "wet dress rehearsal" — a practice run of the most important prelaunch activities, including fueling up the SLS.
The Artemis 1 wet dress rehearsal began on Friday (April 1) at Launch Pad 39B at NASA's Kennedy Space Center (KSC) in Florida. The test was scheduled to wrap up on Sunday evening (April 3), but a problem with the fan system on the SLS' mobile launch tower forced the team to delay the bulk of Sunday's planned work, which included rocket fueling and several simulated countdowns, until Monday (April 4). And a stuck vent valve on the tower stymied Monday's attempt, which was scrubbed after fueling began.
The Artemis 1 team will get a bit of a break before trying again, we learned today (April 5).
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The wet dress is on hold until the private Ax-1 astronaut mission launches from KSC's Pad 39A, NASA officials explained during a call with reporters today. Ax-1, which was organized by Houston-based company Axiom Space, will send three paying customers and one Axiom employee to the International Space Station aboard a SpaceX Dragon capsule. The 10-day mission is scheduled to launch on Friday (April 8) from KSC's Pad 39A, which is next to Pad 39B.
Ax-1 was targeting a Sunday (April 3) launch before it was delayed by a few days to accommodate the Artemis 1 wet dress rehearsal; now the tables have turned.
"We'll fall in behind them," Mike Sarafin, Artemis mission manager at NASA headquarters in Washington, said during today's call, referring to Ax-1.
"Exactly what date that is, we've got to finish sharpening the pencil on our open work," he added. "But we don't anticipate that it'll be too much longer than that after the launch."
The Artemis 1 team managed to complete one of the wet dress rehearsal's two primary objectives and three of its five secondary objectives before running into the issues on Sunday and Monday, said Artemis launch director Charlie Blackwell-Thompson, of the Exploration Ground Systems Program at KSC.
Engineers and technicians won't have to start everything all over again, she added. The first attempt was actually slated to span about four days, after accounting for two days of prep work to get ready for the April 1 kickoff, she noted.
"So, this time, we're looking at something significantly shorter — I would say something in about a 36-hour timeframe," Blackwell-Thompson said.
She and other NASA officials stressed that the Artemis 1 SLS and Orion are in good condition (despite several lightning strikes to Pad 39B on Saturday), and that the issues that have emerged are run-of-the-mill rather than concerning.
"Most of the stuff we're picking up is small or procedural in nature. Some of it is, we need to adjust some of the limits slightly or some of the sequencing or timing slightly," Sarafin said. "Right now, we're not tracking anything significant."
Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or on Facebook.