Technical issues delay the first launch of NASA's new Moon rocket

NASA's uncrewed Artemis I launch of the Space Launch System rocket and Orion capsule was called off on Monday.

Why it matters: NASA plans to use the SLS rocket and Orion to return people to the Moon for the first time since the end of the Apollo program in the 1970s.

The latest: An engine issue prevented the SLS from getting off the pad in Kennedy Space Center in Florida.

One of the rocket's four engines didn't get up to the correct temperature, preventing the space agency from launching.

NASA has backup launch dates on Sept. 2 and Sept. 5, but it wasn't immediately clear whether the space agency would be able to fix the issues and target one of those days.