The countdown is on for a mission to Mars launching from the Space Coast.

For the first time, a spacecraft may be able to help us understand climate change on the red planet and if Mars was ever capable to sustain life.

Standing 188 feet tall, the Atlas V rocket rolled out of the Vertical Integration Facility Saturday morning.

The rocket and MAVEN spacecraft are scheduled to launch Monday afternoon from launch pad 41 at Cape Canaveral Air Force Station.

MAVEN is the first mission dedicated solely to studying the Martian upper atmosphere.

"There's geological evidence that, at one time, Mars had a wet, warm climate,” said NASA Communications Officer Nancy Neal Jones. “But now it's cold and dry, so what happened? Where did the atmosphere go? Where did the water go? And that's what we're trying to find out."

Scientists believe the sun is a big culprit behind the extreme climate change on Mars--and MAVEN will help us learn more about that relationship.

NASA hopes MAVEN will help pave the way for humans to eventually travel to the red planet. The space agency is targeting the 2030s to send humans to Mars.

"When we put humans on Mars, we really want to understand what the environment is like and what has happened in the past," Jones said.

But before MAVEN can do all that, it needs to get off the ground.

It's never easy to launch a rocket, let alone one headed to another planet. But United Launch Alliance is prepared.

"The MAVEN launch is a continuation of the heritage that we've had at ULA in launching Mars missions,” said Chris Chavez from United Launch Alliance. “We actually launched NASA's first successful mission in 1964 and have since launched all of the other major Mars missions."

Once launched, MAVEN will take 10 months to get to its new home planet, helping understand our celestial neighbor next door.

The two-hour launch window opens up at 1:28 p.m. Monday. There is a 60 percent chance of favorable weather conditions at the time of liftoff.