CAPE CANAVERAL, Fla., Sept 4 – For the second time in a week, NASA on Saturday aborted an attempt to launch its giant next-generation rocket ship, citing a stubborn fuel leak that the space agency said could delay the debut of the mission of its Artemis program from the Moon to Mars by at least a few weeks.
Preflight operations were called off for the day about three hours before 2:17 p.m. EDT (1817 GMT) target launch time for the 32-story Space Launch System (SLS) rocket and its Orion capsule from Cape Canaveral, Florida.
The uncrewed test flight, aimed at launching a capsule to the Moon and back, was to mark the inaugural voyage of both SLS and Orion half a century after the last Apollo lunar mission, the predecessor to the Artemis program.
The countdown was cleared after Kennedy Space Center technicians made three unsuccessful attempts to repair a “major” leak of supercooled liquid hydrogen propellant pumped into the rocket’s core fuel tanks, agency officials said.
The initial launch attempt on Monday was also thwarted by technical problems, including another leaking fuel line, a faulty temperature sensor, and cracks in the insulating foam.
Mission managers proceeded with a second launch attempt on Saturday once the previous problems were resolved to their satisfaction. And NASA has set aside another backup launch time, either Monday or Tuesday, in case a third attempt is needed.
But after reviewing data from the latest problems, NASA concluded that the new hydrogen leak was too complex and time-consuming to complete troubleshooting and repair on the launch pad before the mission’s current launch period expires on Tuesday.
The delay means the closest opportunity to try again will come during the next launch period, which runs Sept. 19-30, or during the following October window, NASA Associate Administrator Jim Free told reporters at an afternoon briefing.
He said the delay would also include returning the spacecraft to its assembly building, under Cape Canaveral’s “range” rules that limit how long a rocket can remain on its launch tower before undergoing another round of indoor safety checks.
Mike Sarafin, manager of NASA’s Artemis mission, said efforts to resolve the latest technical snag will require “several weeks of work.”
Earlier in the day, NASA chief Bill Nelson said the return would delay another launch attempt until at least mid-October, in part to avoid a scheduling conflict with another International Space Station crew due to launch earlier that month.
Launch-day delays and disruptions are not uncommon in the space business, especially with new rockets like NASA’s Space Launch System, a complex vehicle with a set of pre-liftoff procedures that must be fully tested and rehearsed by engineers without problems.
On average, the odds of a launch being scrubbed on any given day for any reason, including bad weather, are about one in three.
“We’re not going to launch until it’s right, and that’s the standard operating procedure and will continue to be,” Nelson said at the briefing.
The last-minute launch pad setbacks came at the end of a development program more than a decade in the making, with years of delays and billions in cost overruns under NASA’s respective SLS and Orion contracts with Boeing Co ( BA.N ) and Lockheed Martin Corp ( LMT.N.).
THE MOON ON MARS
Beyond the technical challenges, Artemis I signals a major turning point for NASA’s post-Apollo human spaceflight program after decades focused on low Earth orbit with the space shuttles and the International Space Station.
Named after the goddess who was Apollo’s twin in ancient Greek mythology, Artemis aims to return astronauts to the lunar surface as early as 2025, although many experts believe that time frame is likely to shift.
Twelve astronauts walked on the moon during the six Apollo missions between 1969 and 1972, the only space flights to date that have not placed humans on the lunar surface. But Apollo, born out of the US-Soviet space race during the Cold War, was less scientifically driven than Artemis.
The New Moon program has enlisted commercial partners such as SpaceX and the space agencies of Europe, Canada, and Japan to eventually establish a long-term lunar operating base as a springboard to even more ambitious human journeys to Mars.
The launch of the SLS-Orion spacecraft is a key first step. Its maiden voyage is intended to put the 5.75 million-pound vehicle through its paces in a rigorous test flight that pushes its design limits and aims to prove the spacecraft is fit for astronaut flight.
If the mission is successful, a crewed Artemis II round-trip flight could come as early as 2024, followed within a few years by the first landing of astronauts, including a woman, on the moon with Artemis III.
Billed as the world’s most powerful and complex rocket, SLS represents the largest new vertical launch system NASA has built since the Apollo-era Saturn V.
Although there will be no humans on board, Orion will carry a simulated crew of three — one male and two female dummies — equipped with sensors to measure radiation levels and other stresses that real astronauts would experience.