The next launch attempt could be as early as Friday.

This morning, the first official spaceflight of NASA’s burgeoning Artemis Program, which intends to land the first new vessel on the Moon after multiple decades, was scheduled to launch. The Artemis I was on the launchpad and preparing to go, but unfortunately, the operation needed to be scrubbed at the last minute after mission control detected an issue with one of its four rocket engines.

Safety is always first. Following today's #Artemis I launch attempt, @NASAArtemis teams are working through an issue with engine number 3, and expect to give a news briefing later today. Stay tuned for broadcast details. https://t.co/z1RgZwQkWS pic.twitter.com/BxpIOGyId9

— NASA (@NASA) August 29, 2022

“Launch controllers were continuing to evaluate why a bleed test to get the RS-25 engines on the bottom of the core stage to the proper temperature range for liftoff was not successful, and ran out of time in the two-hour launch window,” NASA explained in an update. “Engineers are continuing to gather additional data.”

While the last minute cancellation was disappointing, NASA engineers have stressed that they absolutely cannot launch a vessel until they are reasonably sure of its success and safety. As Artemis I is slated to be a benchmark for the rest of the mission, they need to get its initial launch as close to perfect as they can manage.

NOW: NASA Administrator @SenBillNelson speaks about today's #Artemis I launch attempt. https://t.co/l65YUBc4KI

— NASA (@NASA) August 29, 2022

“We don’t launch until it’s right,” said NASA Administrator Bill Nelson. “They’ve got a problem with the gases going on the engine bleed on one engine. It’s just illustrative that this is a very complicated machine, a very complicated system, and all those things have to work. You don’t light the candle until it’s ready to go.”