NASA delayed the much-anticipated launch of its Space Launch System rocket and uncrewed Orion capsule on Saturday.

The latest: NASA says it won't be able to launch the SLS before late September or October, opting to stand down and fix the issues that scuttled liftoff on Saturday.

Why it matters: NASA is hoping to use this rocket and capsule to one day return people to the surface of the Moon for the first time since the 1970s.

Catch up quick: The space agency decided to call off the launch after a hydrogen leak popped up during fueling that they weren't able to correct in time to get off the pad.

• Mission controllers attempted to fix the leak multiple times, but they weren't able to resolve it.
• NASA engineers are planning to make a decision on how best to fix the issue early next week.
• "We're not going to launch until it's right," NASA administrator Bill Nelson said during a post-scrub press conference Saturday.
• This delay comes after technical issues scrubbed an earlier launch attempt on Monday.

The big picture: NASA is planning to send people back to the lunar surface in 2025, with multiple SLS launches scheduled between now and then.

• This mission, called Artemis I, is designed to test out systems that will be needed to safely send people to the Moon.
• For this flight, the SLS is expected to send Orion on a journey around the Moon before the capsule comes back in for a landing on Earth, splashing down in the Pacific Ocean.

Editor's note: This story has been updated with new information about the SLS' next launch attempt.