It has been moving at a rapid five centimeters per second.

Rapid five centimeters per second.

It should be docking within the next 30 seconds, less than 30 seconds.

It's taking place nearly 15 hours after its successful launch from Cape Canaveral yesterday and after NASA discovered two additional helium leaks during the voyage late last night.

With us as we await this milestone, CNN space and defense correspondent Kristen Fisher and retired NASA astronaut Leroy Chow.

Kristen, first talk to us about what's actually happening right now, seconds away from this dock.

Yeah, they've actually extended it to just about a few minutes because they want to make sure the light is right.

So what you have is Boeing Starliner spacecraft.

That's that capsule that the astronauts that we watched launch yesterday have been inside for the slowly approaching the International Space Station and they're going to dock.

But this is the first time they have ever done that with a crew on board.

And of course, you have astronauts and cosmonauts aboard the International Space Station.

And so what they want to do is take it very slowly and they want to wait until there's actual sunlight on the Boeing Starliner spacecraft.

Right now, they're in a period of darkness, nighttime in space.

So they're waiting just a And they've been troubleshooting these pesky RCS thrusters, as they're called, the things that kind of propel the spacecraft do those last minute final adjustments.

But they think they've walked, they've worked through those issues.

And we're now just minutes away, nine meters away as well as five centimeters at a go.

It's going to still be a second here.

I'd also prefer driving during the day to driving at night.

So that makes complete sense to me.

We're watching every little thing with this, right?

So we're watching those thrusters.

This was a slight delay compared to when it was supposed to dock, but also these little helium leaks.

What's going on here?

Yeah.

So we knew there was a helium leak before launch.

NASA and Boeing was aware of it and they said, Hey, you know what?

We think it is within our parameters that it's still safe to fly.

So we knew there was going to be one, but once the spacecraft got into orbit, they found two more.

And so last night before NASA astronauts, Butch Wilmore and Sonny went to sleep, uh, they made them do all these things to kind of shut down some of these thrusters to stop the leak.

And, um, they troubleshooted it overnight and decided that they were okay and go for this docking today.

So, um, it could have been more serious, but turned out not to be.

And so now they're, uh, you know, just troubleshooting these final things.

It's a first test flight.

These things do happen, but you know, it's not a serious, serious issue.

We just got word from the from docking Leroy.

As we're watching this unfold, take us inside the minds of these astronauts about to accomplish something historic.

Oh, absolutely.

Butch and Sonny are consummate professionals.

They're very laser focused on the task at hand.

Docking is one of those critical maneuvers.

And so, you know, they're watching their, their instruments.

They're, they've got their, their check checklists out and they are just monitoring the situation, monitoring the automatic situation, poised to take manual control if necessary.

And again, they're delayed just a little bit just to wait for optimal lighting conditions.

Not a big deal.

Tell us what we're looking at here.

Are you able to see the picture as we're looking at the capsule moving towards the space station?

Yes.

So I have an image of the capsule as it's not at all like the movies.

You don't come whizzing in and dock.

It takes, takes a bit of time.

You know, you've got to be, got to be slow and deliberate.

Anyway, by the, by the way, I mean, I'm very familiar with this process.

On my mission in the Russian Soyuz capsule, we had an emergency during docking and we had to execute a manual night docking, you know, so we, we didn't wait for the lighting conditions, but.

Leroy, look at that.

I think it docked.

Is this, is this a success?

Yeah.

It's looking like it, right?

Yeah.

All right.

I believe so.

So that's a huge deal.

We're waiting with bated breath for confirmation that they've docked.

It was, it was slow and it was tedious, but it appears to have been successful.

So Leroy put this docking into context for us.

What it means for the bigger picture of space travel.

Well, what it means is that if they've successfully docked and it seems like they have awaiting that confirmation, as you said, but that means that we now have a second path to launching NASA astronauts to and from the ISS.

Of course, SpaceX has been doing it for nearly three years.

We want NASA likes redundancy, astronauts like redundancy, all engineers do.

And so this would mean we have a second path without having to go back relying on the Russians and their Soyuz vehicles.

So this is a historic moment.

Butch and Sonny, I'm sure they're, you know, going through their procedures, but they're, they're also thrilled to, to be attached to the ISS.

Yeah.

Not the least because that's not a giant capsule they're in, right?

I'm sure they're looking forward to stretching their legs.

Oh yeah.

Yeah.

No, it's not a, not a big capsule by any means.

Space shuttle by comparison was, was a palace, right?

I mean, we could have seven astronauts with our seats deployed and still be very much in more of a business class type of seating arrangement, but but nonetheless these vehicles are very capable and they do their job well and hopefully everything else will continue to go relatively smoothly for this flight test.

Absolutely.

Kristen, what happens next?

Well, what happens next is these astronauts are going to spend about eight days up at the international space station.

But in addition to them bringing themselves and this new spacecraft, they've also brought a new replacement pump to fix the machine that recycles, get this, the astronaut urine and turns it into drinking water.

It's been broken for a few days now.

So as you can imagine, there have quite literally been and so right now inside that Boeing Starliner spacecraft is a replacement pump for that urine recycling system.

A critical piece of infrastructure that's needed on board the ISS.

Unquestionably so.

A critical mission.

Oh my gosh.

I'm sure that the crew there was excited to see Sonny and Butch anyways, but they're going to get like a hero's welcome.

Oh yeah.

Kristen Leroy, thank you so much to both of you.

A huge day.

It was great to witness.

Even though the audio wasn't great, it was great to watch that happen.

Yeah.

Very slow and perfect.

Meticulous.