NASA aims for the moon, again, with Saturday launch

Second time could be the charm for the first-ever launch of NASA’s towering moon rocket.

After an engine temperature-related scrub earlier this week, NASA is now set to launch its Space Launch System rocket and Orion capsule Saturday on an uncrewed mission around the moon. The launch is set for 11:17 a.m. Pacific time from Kennedy Space Center in Florida.

Saturday’s launch is the first of a series of moon missions NASA has dubbed the Artemis program. The space agency’s ultimate goal is to prepare for future Mars missions by establishing a long-term presence on the moon that will help astronauts learn to live and work in space.

NASA intends to send a crew around the moon on the Artemis II mission, which will launch no earlier than 2024. Then by 2025 or later, the space agency is set to land the first woman and first person of color on the moon.

But to get to those more complex crewed missions, NASA had to work through the issues that led to the scrub Monday.

NASA officials called off that launch because a sensor indicated that one of the four engines in the SLS rocket’s core stage was not chilling down to the correct temperature, which is crucial to performance.

NASA engineers also investigated a hydrogen leak in a connector that helps fuel the rocket before liftoff.

On Thursday, NASA officials said they fixed the leak by replacing a hose and loose-pressure sensor line and tightened the bolts around the seal. NASA also determined that the sensor detecting engine temperature was faulty. Engineers will instead rely on data from other indicators to make sure the engine temperature is cold enough, John Honeycutt, NASA program manager for the SLS rocket, told reporters Thursday.

“We don’t take chances, especially on such a huge, powerful rocket,” said Dava Newman, director of the MIT Media Lab and a former NASA deputy administrator. “Everything has to work perfectly.”

Scrubs are very common, particularly with new rockets, said Ramon Lugo, former deputy program manager of the launch services program at NASA’s Kennedy Space Center.

Space shuttle missions often endured multiple scrubs before launch, Newman noted.

“Safety is always first with launch,” she said. “You have to be patient, you have to persevere.”

NASA will need to analyze the data from this flight since it will be the only launch of the SLS rocket before humans are onboard.

“A scrub is a relatively small thing, and it demonstrates the fact the team is focused on doing the right thing,” Lugo wrote in an email.

The SLS rocket will propel the uncrewed Orion capsule 280,000 miles from Earth to a distant orbit around the moon. The capsule is set to splash down in October off the coast of San Diego.

The 37-day mission is intended to push the capsule to its limits to ensure it’s ready to carry a crew.