(KTEN) — NASA is launching a new chapter in space exploration with the Artemis I mission, the first phase of a new program paving the way for humans to return to the to the moon... and travel beyond. The spacecraft was scheduled to lift off Monday morning, but the launch was scrubbed due to a problem with one of the rocket's four engines.

"Artemis I is the stepping stone of the entire Artemis project," explained Liliana Villarreal, the operations flow manager in Exploration Ground Systems at NASA's Kennedy Space Center in Florida. "This is the first time that we're going to be launching the SLS rocket and the Orion spacecraft. The SLS rocket is going to launch Monday and position the spacecraft on its way to the moon, and we're going to be out there for 38 to 42 days before we land back."

Artemis I is the first in an entirely new set of missions for NASA. Villarreal explained how it will get the United States ready to send humans back to the moon and on to Mars.

"Artemis I is a test flight to test all the systems; to make sure that we're ready to put people in the vehicle," she said. "Artemis II is our first manned flight, and we're going to be going around basically like Apollo 8 did, and then we did Apollo 11 where we landed on the moon. Artemis III is our moon landing, and we're going to have the first woman and first person of color to land on the moon. We are partnering with SpaceX, who's going to provide us the human lander for that mission."

And how does the new Artemis program differ from the Apollo program?

"It's the same mission with going to the moon. How we get there is different, and the capabilities that we have are different," Villarreal said. "It's a more advanced vehicle; it can stay in space longer than Apollo could. It's meant to be able to go and orbit the moon and land on the moon. It's really a marvelous vehicle. We've been working on it for about 2.5 years when the pieces first started coming in and we put it all together, and we're ready to test it and launch it!"