NASA managers review readiness for Artemis moon rocket launch on Wednesday

Engineers made final preparations Sunday for the overnight start of another countdown to launch for NASA’s leak-bedeviled Artemis moon rocket, setting the stage for a third attempt Wednesday to get the $4.1 billion booster and Orion crew capsule into space for an unpiloted maiden flight.

After multiple delays due to hydrogen fuel leaks and other glitches, along with the rocket’s nail-biting brush with Hurricane Nicole last week, NASA managers met Sunday to review launch preparations and the team’s readiness to begin a 47-hour 40-minute countdown with a traditional “call to stations” at 1:24 a.m. EST Monday.

If all goes well, the launch team will begin pumping 750,000 gallons of supercold liquid oxygen and hydrogen fuel back into the huge rocket’s tanks starting just before 4 p.m. Tuesday, using revised “kinder, gentler” techniques to control temperatures and minimize sharp pressure jumps to prevent leaks in critical seals.

If any problems do show up, engineers will have two hours to resolve them before the launch window closes.

But the weather is 90% “go” and, if the fueling procedures work as intended, the 322-foot-tall Space Launch System rocket’s four shuttle main engines and extended strap-on solid-fuel boosters should finally roar to life at 1:04 a.m. Wednesday, opening a new era in American space flight.

Briefly turning night into day as it climbs away atop 8.8 million pounds of thrust, the 5.7-million-pound SLS will quickly accelerate as it consumes propellants and loses weight, surpassing the speed of sound in less than one minute.

The two strap-on boosters, which provide the lion’s share of the rocket’s initial thrust, will burn out and fall away about two minutes and 10 seconds after liftoff. The four hydrogen-fueled engines powering the core stage will shut down six minutes later, putting the Orion capsule and the SLS second stage into an initial elliptical orbit.

After raising the low point of the orbit, the single engine powering the Interim Cryogenic Propulsion Stage, or ICPS, will fire again about 90 minutes after launch to break out of Earth orbit and head for the moon. The Orion capsule and its service module will separate a few minutes later to continue the rest of the trip on their own.

The goal of the Artemis 1 mission is to send the Orion spacecraft on a looping trajectory beyond the moon in a critical test of the vehicle’s propulsion, navigation and solar power systems before returning to Earth for a 5,000-degree re-entry and splashdown in the Pacific Ocean west of San Diego.

If the Artemis 1 flight goes well, NASA plans to launch four astronauts atop a second SLS for a lunar shakedown mission — Artemis 2 — in late 2024, followed by an astronaut landing mission in the 2025-26 timeframe.

But that assumes the Artemis 1 flight goes well. As Jim Free, director of exploration systems at NASA Headquarters, put it Friday, “we’re never going to get to Artemis 2 if Artemis 1 isn’t successful.”

William Harwood

Bill Harwood has been covering the U.S. space program full-time since 1984, first as Cape Canaveral bureau chief for United Press International and now as a consultant for CBS News. He covered 129 space shuttle missions, every interplanetary flight since Voyager 2’s flyby of Neptune and scores of commercial and military launches. Based at the Kennedy Space Center in Florida, Harwood is a devoted amateur astronomer and co-author of “Comm Check: The Final Flight of Shuttle Columbia.”