CAPE CANAVERAL, Fla. (WHNT) – NASA’s newest rocket will be launching later than expected.

Due to an issue with Engine 3 on the Space Launch System core stage, NASA decided to scrub (cancel) the launch at 7:36 a.m. CT.

The first of two backup launch windows is this Friday, September 2 from 11:48 a.m.-1:48 p.m. CT. Artemis I’s 42-day mission would be shortened to 39 days if launched during this window.

Artemis Mission Manager Mike Sarafin confirmed the Friday launch window is still on the table; teams are aiming for a 96-hour (four-day) re-cycle of the SLS. When prompted for more, Sarafin simply told reporters “There’s a non-zero chance we launch Friday.”

If the mission launches during the second backup window, Monday, September 5 between 4:12 and 5:43 p.m. CT, Artemis I will be on a 42-day mission.

The team worked three issues during Monday morning’s attempt. Besides the Engine 3 issue, teams were also working on what was thought to be a crack in one of the core stage’s tanks. Ice had formed on the rocket, alerting teams to the issue. However, engineers discovered air had seeped into a seam between the foam protection on the core stage and was being chilled by being close to the super chilled propellant in the tank. Because the air had not breached the tank itself, engineers declared the issue resolved.

During fueling operations early Monday morning, two liquid hydrogen leaks were detected, however, those issues were resolved.

Specifically, the issue with Engine 3 was a conditioning issue. Conditioning is a standard procedure in which controllers increase pressure on the core stage tanks to bleed some super chilled propellant to the engines, chilling them down to the proper temperature range for startup.

During a news conference Monday afternoon, Artemis Mission Manager Mike Sarafin said the teams also discovered a leak in an SLS intertank vent valve at the same time as the Engine 3 issue. This made the balancing act of keeping intertank pressure and trying to condition Engine 3 even more difficult, he explained. And even if Engine 3 was able to get conditioned, Sarafin said crews were working against a “no-go” for weather. At the start of the window, precipitation was too close to the Kennedy Space Center; at the end, there was too much lightning to launch.

The one-time Acting Director of Marshall Space Flight Center, NASA Veteran Gene Goldman, says scrubs happen regularly on rocket launches, and on a test flight like Artemis I, it’s not surprising.

“We didn’t meet the launch commit criteria for the flight those launch criteria are established on the bases of protecting the crew and protecting the vehicle. everything to is try to work out the types of issues from the moment you have from the moment you start tanking until the time you lift off and then throughout the operation of the mission.”

Artemis I is an uncrewed test flight, slated to send the Orion crew capsule into orbit around the moon and gather data ahead of a crewed mission. If Artemis I is successful, Artemis II could launch as soon as 2024. This crewed test flight will send four astronauts on a lunar fly-by of the Moon (similar to Apollo 10), with Artemis III – scheduled for as soon as 2025 – putting the first woman on the Moon, as well as being the first mission to explore the Moon’s south pole.