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In just days, humans could get closer to the moon than they have in over half a century.

The last astronaut to ever walk on the lunar surface was Apollo 17 astronaut Gene Cernan.

We leave it. We came with peace and in hope for all manned.

He and his crewmates left the moon in December 1972.

Since then, no one has ventured so far out into space.

Now, though, NASA is poised to launch four astronauts on the Artemis II mission.

The plan is to fly around the moon in a bell-shaped capsule before coming back and splashing down into the Pacific Ocean.

The mission's commander is NASA astronaut Reid Wiseman.

He emphasized that this is a test mission.

When we get off the planet, we might come right back home.

We might spend three or four days around Earth. We might go to the moon. That's where we want to go, but it is a test mission. So what kind of test mission is it? And what could it mean for NASA's long-term moon plans? To answer those questions, we're checking in with NPR science correspondent, Nell Greenfield Boys, who's at the Kennedy Space Center in Florida right now. Hey, Nell. Hey there, Gina. It is so cool that you're there for the launch. I'm very jealous. So where are you right now? Like, can you see the rocket that's going to blast off? Yeah, they have us out here at the press center, which is away from the rocket. So I can see it, but it looks tiny out there. I mean, in reality, it's 322 feet tall, but it's this, you know, orange and white rocket. And from where I am, I can see it along with the big countdown clock, you know, which is under this American flag. And you've got all the press trucks set up everywhere.

And, you know, it's a big to-do.

There'll be more people pouring in as we get closer to the launch.

Wow.

Okay.

So it's my understanding that the earliest this mission can launch is today, Wednesday the first.

And this is the start of the launch window, right?

That's right. Yeah. So the earliest is 6.24 p.m.

Eastern time on Wednesday, April 1st. But it could be delayed by anything. There could be weather rolling in.

There could be technical glitches, like maybe a hydrogen leak. And if they have to delay, it depends on what the nature of the problem is, but it takes

like 24 to 48 hours to get things reset up so they can try again.

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