CAPE CANAVERAL, Fla. - NASA will try again Tuesday to complete a critical test for its Artemis 1 mega moon rocket mission after technical problems delayed it twice last week.
The countdown test will be modified because of a faulty helium valve. NASA says it plans to start the "wet dress rehearsal" Tuesday and finish it Thursday.
Launch managers tried twice — once Sunday and again Monday — to load nearly 1 million gallons of fuel into the 322-foot (98-meter) rocket known as Space Launch System, or SLS. Balky fans at the launch pad thwarted the first effort; the valve halted the second attempt.
A severe thunderstorm resulted in four lightning strikes at the pad Saturday, but officials did not believe that caused any of the technical problems. They described the problems as nuisances — not design issues.
"The rocket is fine. The spacecraft (capsule) is fine. We've just got to get through the test and the test objectives," mission manager Mike Sarafin told reporters.
The countdown test is the last major milestone before the rocket's long-awaited launch debut. The Orion crew capsule atop the rocket will be hurled to the moon in a passenger-less test flight, looping around but not landing before returning to Earth. NASA is targeting June, depending on how the demo goes.
"We didn’t get through everything we wanted, but certainly learned a great deal that we’ll take into our next attempt," said NASA's Jim Free, who's in charge of exploration systems development.
Artemis 1 mission (NASA)
After this first moonshot in NASA's Artemis program, NASA will send a crew around the moon in 2024 and then attempt the first lunar landing by astronauts in 2025 or so. Astronauts last walked on the moon in 1972 during NASA's Apollo program.
NASA expects to announce the crews for the initial lunar missions this summer. The pool of candidates includes nine men and nine women; two are at the International Space Station and two are due to arrive there in a few weeks.
Twenty-four astronauts flew to the moon during Apollo from 1968 through 1972; 12 landed on the lunar surface.
Unlike Apollo, NASA is partnering with private business for its moon program, named Artemis after Apollo's twin sister in Greek mythology. While NASA's rocket and capsule will get astronauts into lunar orbit, SpaceX's still-in-development Starship will carry them down to the lunar surface, at least for the first mission. NASA is seeking additional companies for later landings.
The space agency's goal is to develop a sustainable moon presence, then aim for Mars. NASA Administrator Bill Nelson recently cited 2040 as the target for a Martian expedition with astronauts.