NASA to roll Artemis 1 moon rocket back out to pad for testing in early June

NASA will roll its Artemis 1 moon rocket back out to the launch pad early next month, if all goes according to plan.

The Artemis 1 vehicle — a giant Space Launch System (SLS) rocket with an Orion crew capsule on top — is scheduled to return to Pad 39B at NASA's Kennedy Space Center (KSC) in Florida in early June for another try at a crucial "wet dress rehearsal" test, agency officials wrote in an update on Friday (May 20).

The wet dress will run the SLS and Orion through a series of prelaunch checks and procedures, including fueling of the rocket and several simulated countdowns. And next month's attempt won't be Artemis 1's first crack at it.

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NASA first rolled the Artemis 1 stack out to Pad 39B from KSC's Vehicle Assembly Building (VAB) in mid-March for a wet dress try that began on April 1. That attempt was supposed to end two days later, but it was delayed and ultimately halted by a series of issues, including a stuck valve on the vehicle's mobile launch tower and a hydrogen leak in an "umbilical" line connecting the tower to the rocket. 

NASA rolled the Artemis 1 stack off Pad 39B and back into the VAB on April 25 to investigate and fix those problems. That work is now pretty much done, as are onsite repairs made by the private contractor that's supplying gaseous nitrogen for the Artemis 1 test and launch campaign, agency officials said. (Gaseous nitrogen is used to purge oxygen from the SLS prior to fueling operations, for safety purposes, during wet dress and launch.) 

"Following completion of a few remaining verifications, teams will retract platforms inside the VAB to prepare SLS and Orion to roll out to pad 39B," they wrote in Friday's update. "Plans call for the next wet dress rehearsal to take place about 14 days after the rocket arrives at the pad."

The wet dress is designed to show that Artemis 1's SLS and Orion are ready to launch on an uncrewed round-the-moon mission, the first liftoff of NASA's Artemis program of lunar exploration. The agency aims to launch the roughly month-long Artemis 1 this summer, though it won't set a target date until the wet dress is done and the resulting data analyzed.

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.