After working around a hydrogen leak, NASA pressed ahead with a “wet dress” rehearsal countdown of its Artemis II moon rocket Monday, loading the huge rocket with more than 750,000 gallons of liquid oxygen and hydrogen fuel, only to be derailed by additional leakage early Tuesday.Already running several hours behind schedule, the countdown resumed at the T-minus 10-minute mark around 12:09 a.m. EST Tuesday, ticking down toward a simulated engine start.But four-and-a-half minutes later, the countdown stopped again due to a “liquid hydrogen leak at the interface of the tail service mast umbilical, which had experienced high concentrations of liquid hydrogen earlier in the countdown,” NASA said on social media.AdvertisementAdvertisementThe Space Launch System rocket’s mobile launch platform is equipped with two tail service masts, large side-by-side structures at the base of rocket that house propellant lines leading to pull-away umbilical assemblies on a side of the booster’s engine compartment.”The launch control team is working to ensure the SLS rocket is in a safe configuration and (to) begin draining its tanks,” NASA said.Whether mission managers will be able to clear the rocket for launch as early as Sunday to propel four astronauts on a flight to the moon will depend on the results of a detailed overnight review and post-test analysis. But NASA only has three days — Feb. 8, 10 and 11 — to get the mission off this month or the flight will slip to March.Hydrogen leaks have proven extremely difficult to repair at the launch pad, and a Super Bowl Sunday launch appears unlikely unless managers conclude the leak is manageable as is. But no final decisions on a path forward are expected until engineers have a chance to review the data. A news briefing is expected at 1 p.m. Tuesday.AdvertisementAdvertisementThe practice countdown began Saturday evening — two days late because of frigid weather along Florida’s Space Coast and, after …
