Artemis 1 will use NASA’s new Space launch system (SLS) megarocket to send an unfilled Orion capsule to lunar orbit and back. NASA attempted to launch the epic mission on Saturday (September 3), but was called off when it was unable to cope with supercooled liquid hydrogen leak propellant (LH2) in time for launch. The leak occurred at a “quick disconnect,” an interface that connects the SLS core stage to a propulsion line coming from the giant rocket’s mobile launch tower. After analyzing the issue for a few days, the Artemis 1 team decided to replace the seal in the fast disconnect misbehavior, agency officials announced in a update Tuesday afternoon (opens in new tab) (September 6). This work will be done on Pad 39B at Kennedy Space Center (KSC) in Florida, where the Artemis 1 stack has been climbing for the past three weeks. “Performing the work on the pad requires technicians to create an enclosure around the work area to protect the material from weather and other environmental conditions, but allows engineers to test the repair under cryogenic or ultracold conditions,” they wrote. NASA officials at the Tuesday Briefing. “Performing the work on the pad also allows the teams to gather as much data as possible to understand the cause of the problem,” they added. “Teams can return the rocket to the Vehicle Assembly Building (VAB) to perform additional tasks that do not require the use of the cryogenic facilities available only on the pad.” And a rollback to the VAB may be required whether the team wants to perform more repairs there or not. The US Space Force has certified Artemis 1’s Flight Termination System (FTS), which would destroy the rocket if it went off course during liftoff, for just 25 days. (The Space Force oversees the Eastern Range, the vast rocket launch area that includes KSC.) That deadline will have passed on Sept. 19, when the next Artemis 1 launch window opens. Recertification requires FTS testing, which can only occur at VAB. NASA officials have said they may apply for another waiver to extend the certification period, which would allow Artemis 1 to stay on the pad longer, but it’s unclear at this time whether they will do so. (Artemis 1 has already received such a waiver, from 20 days to 25.) Saturday’s scrub was the second for Artemis 1. The first, which it happened on August 29th, was prompted by a measurement showing that one of the four engines in the SLS core stage was not cooled to the proper prelaunch temperature. The Artemis 1 team quickly concluded that the reading was caused by a faulty temperature sensor and decided to go ahead with a Saturday attempt. The team also had a problem with an LH2 leak during the August 29 attempt, but that was much smaller than the leak the team is working on now. Artemis 1 has two launch windows over the next two months. The first will run from September 19 to October 4 and the second is open from October 17 to October 31. A reset to VAB would almost certainly give the Sept. 19-Oct. 4 window inaccessible. 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 extraterrestrial life. Follow him on Twitter @michaeldwall (opens in a new tab). Follow us on Twitter @Spacedotcom (opens in new tab) or enabled Facebook (opens in a new tab).
