NASA still aims to launch its Artemis 1 moon rocket on Wednesday (Nov. 16), but a few boxes must be checked first.
Artemis 1, which will send an uncrewed Orion capsule to lunar orbit using a Space Launch System (SLS) rocket, is scheduled to lift off from Florida's Kennedy Space Center (KSC) Wednesday during a two-hour window that opens at 1:04 a.m. EST (0604). And the mission team is confident it can hit that target.
"I feel good headed into this attempt on the 16th," Mike Sarafin, Artemis mission manager at NASA headquarters in Washington, said during a press briefing on Sunday evening (Nov. 13).
"The team is moving forward as one unit," he added. "We've just got some work to do."
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One focus of that work will be a thin strip of caulking called RTV that encircles Orion. The RTV helps smooth out a small indentation in the capsule that could potentially cause some unwanted circulation and heating of air during flight, Sarafin said.
Hurricane Nicole tore some of that caulking loose on Thursday (Nov. 10) when it slammed into Florida's Space Coast, mission team members said. (The Artemis 1 stack endured the wrath of Nicole, which weakened to a tropical storm shortly after landfall, out in the open on KSC's Pad 39B.)
It's possible that some of the storm-torn RTV could shake free during liftoff, creating a debris hazard for the SLS, Sarafin said. The team is still examining the nature and severity of this risk.
"We need to just spend a little more time to review our flight rationale headed into this launch attempt, specifically as it pertains to liberation of any remaining RTV and debris transport," Sarafin said.
The Artemis 1 team isn't terribly concerned about increased "aeroheating" around Orion due to the loss of some RTV, he added.
"We do have protections in place as it pertains to the materials that underlie that RTV," he said. "This is just an additional layer on there to create a kind of a seamless airstream flow."
The RTV issue is not fixable at the launch pad, because Orion sits so high atop the SLS. If the team determines that the caulking needs to be replaced, a rollback to KSC's Vehicle Assembly Building would likely be required.
In addition to the RTV analyses, the team plans to replace an electrical connector near the base of the SLS that's associated with some wonky readings. This can be done at the pad.
Even if the team couldn't replace the connector, however, the issue probably wouldn't prevent an on-time liftoff, Sarafin said, for the rocket has considerable redundancy in its electrical systems.
"We do have some very well written launch-commit criteria that are very well thought out," Sarafin said. These criteria, he added, "would support flying in spite of what this connector may bring. That said, we're hoping to get back to a fully functional capability."
The Artemis 1 team will meet again on Monday (Nov. 14) to discuss these and other issues. They plan to hold another briefing that afternoon, so we'll get an update on the situation and the latest thinking at that time.
Artemis 1 will be the first-ever flight for SLS and the second for Orion, which launched to Earth orbit atop a United Launch Alliance Delta IV Heavy rocket in 2014.
It will also be the first mission in NASA's Artemis program of lunar exploration, which aims to establish a crewed outpost near the moon's south pole by the end of the 2020s.
If all goes according to plan with Artemis 1, Artemis 2 will launch in 2024, sending astronauts on a trip around the moon. Artemis 3 will put boots on the ground near the lunar south pole in 2025 or 2026.
Artemis 1 will last about 26 days if it launches on Wednesday. (Different launch dates lead to different mission durations, thanks to orbital dynamics.) Mother Nature should cooperate; there's a 90% chance of good weather on Wednesday. If Artemis 1 can't fly on that day, NASA has backup dates of Nov. 19 and Nov. 25.
Mike Wall is the author of "Out There (opens in new tab)" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall (opens in new tab). Follow us on Twitter @Spacedotcom (opens in new tab) or on Facebook (opens in new tab).