Fuel leak halts NASA's second shot at moon launch

KENNEDY SPACE CENTER, Florida－NASA's new moon rocket sprang another dangerous fuel leak on Saturday, forcing launch controllers to call off their second attempt to send a crew capsule into lunar orbit with test dummies.

The first attempt on Aug 29 was also marred by escaping hydrogen, but those leaks were elsewhere on the 98-meter rocket, the most powerful ever built by NASA.

The current launch window for the mission ends on Tuesday and is "definitely off the table", James Free, associate administrator for Exploration Systems Development, told a news conference on Saturday.

The next possible launch window is Sept 19 to Oct 4, and failing that, Oct 17 to 31, NASA said.

The ability to take off during those windows "will really depend on the options that the team comes back with likely on Monday or early Tuesday morning", Free said.

Extensive leak inspections and repairs could require that the rocket be hauled off the pad and back into the hangar, and that would push the flight into October, NASA Administrator Bill Nelson said.

"We'll go when it's ready. We don't go until then and especially now on a test flight, because we're going to stress this and test it … and make sure it's right before we put four humans up on the top of it," Nelson said.

NASA wants to send the crew capsule atop the rocket around the moon, pushing it to the limit before astronauts get on the next flight. If the five-week demo with test dummies succeeds, astronauts could fly around the moon in 2024 and land on it in 2025.

Launch director Charlie Blackwell-Thompson and her team had barely started loading nearly 1 million gallons of fuel into the Space Launch System rocket at daybreak on Saturday when the leak cropped up in the engine section at the bottom.

Ground controllers tried to plug it the way they handled previous leaks: stopping and restarting the flow of super-cold liquid hydrogen in hopes of closing the gap around a seal in the supply line. But the leak persisted. Blackwell-Thompson finally halted the countdown after three to four hours of futile effort.

The $4.1 billion test flight is the first step in NASA's Artemis program of renewed lunar exploration, named after the twin sister of Apollo in Greek mythology.

Twelve astronauts walked on the moon during NASA's Apollo program, the last time in 1972.

Agencies via Xinhua