Tip:
Highlight text to annotate it
X
Coming up next on Jonathan Bird's Blue World, Jonathan goes to inner space at NASA's Neutral
Buoyancy Lab, where astronauts are trained.
Hi, I'm Jonathan Bird and welcome to my world!
Blue World takes me on adventures all over the planet. Today’s adventure takes me to
the Johnson Space Center at NASA, in Houston, Texas!
And, I’m standing on the International Space Station!
Well, not exactly. I’m standing on an underwater full size replica of the International Space
Station in a gigantic indoor swimming pool. Here they train astronauts to work in zero
gravity by simulating these conditions underwater.
Outside, it just looks like a huge warehouse, but inside is the Neutral Buoyancy Laboratory:
The NBL.
I arrive early in the morning and meet Daniel Sedej, the facility manager, who has arranged
our visit.
We drag all our gear inside and get our first glimpse of the NBL. This thing is huge—a
swimming pool nearly the size of a football field!
As we arrive, the morning mission briefing is just starting. The entire team, from astronauts
to support divers to technicians, are all given a thorough run-through on the training
exercises for the day. And Cameraman Tim and I are part of this meeting, because they are
going to let us dive in the NBL today with the astronauts!
Our morning starts with a quick checkup. All divers in the NBL must pass a rigorous physical,
and a checkup before the dive. Cameraman Tim and I are no exception.
We pass our checkup, and next we meet up with Sara Williams, the Dive Training Officer who
gives us a dive safety briefing. What to do and what not to do in the NBL.
Just as we finish our briefing, the team is gathering on the deck to begin preparations
for putting the astronauts in the water.
Getting into a space suit is no easy feat. In fact, it might be easier in the zero gravity
of orbit. But here on land, it takes assistance.
The astronauts wear liquid-cooled underwear to keep them from overheating. That’s what
these tubes are for.
The torso of the suit is clamped to a cage because its too heavy to lift. That’s because
this space suit is specially modified for underwater use, and has a lot of lead weight
in it.
Climbing into the torso is a little tricky.
It takes nearly an hour to suit up.
The last thing to go on is the helmet.
Underwater, a high-oxygen blend of air will be fed to the astronauts through their umbilicals.
Meanwhile, the safety divers are in the water getting ready. They wear double scuba tanks
so they have enough air to stay down as long as necessary to complete the mission.
Tim and I are getting ready too. I can’t wait to see this enormous underwater facility!
I descend into the clearest water I have ever seen, and it looks like an underwater movie
set! The pool is a staggering 40 feet deep, and everywhere I look are full-size replica
sections of the International Space Station.
I take a few minutes to explore the pool. I can see from one end to the other very clearly,
meaning that the underwater visibility is over 200 feet! I could spend a few hours just
swimming around down here. It’s like a playground for divers, with all sorts of great structures
to swim through!
For the astronauts--now, the moment of truth. A crane lifts them into the pool, wearing
300 pounds of space suit apiece.
Underwater, the safety divers meet them and carefully remove them from the platform. Each
astronaut is carefully weighted to be precisely neutrally buoyant. (Hey, they don’t call
it the Neutral Buoyancy Lab for nothing!) Once weighted properly, the astronauts hover
in the water as if floating in the weightlessness of space.
Since fins don’t work in space, the astronauts don’t get to wear them here. They must be
moved from task to task by the divers. The divers are also responsible for keeping a
careful eye on everything happening. Each astronaut has 4 divers assigned to him or
her. Two are safety divers. Another has a camera with a cable going to the control room.
And there are more cameras mounted all over the inside of the pool too.
In the Test Director room overlooking the pool, 21 monitors keep the staff informed
of everything that happens below. They oversee the safety of the operation.
If anything were to go wrong, the divers can get the astronaut to the surface in only seconds.
In the Test Conductor room, another team is conducting the training run. The test conductor
and team speak directly to the astronauts through communication gear in their helmets.
But powerful underwater speakers allow the divers to hear everything that is being said,
even if they can’t talk back.
The point of all this effort is to provide a learning environment for astronauts where
they can practice tasks over and over in simulated zero gravity, before they are required to
do it by themselves in space.
Tasks that are easy on land become much harder in zero gravity. And harder still while wearing
a space suit that has to be able to protect an astronaut from the vacuum of space.
A space suit is designed to have more pressure on the inside than on the outside, since it’s
effectively inflated like a balloon in space. Here in the NBL, that pressure is backwards.
Water is definitely not a vacuum. In order to keep the water pressure from squishing
the astronauts as they go deeper, the suits are inflated to a pressure just a few PSI
higher than the surrounding water.
When an astronaut goes deeper into the pool, the water pressure pushes in on the suit and
tries to compress it, so the suit is given more internal pressure to keep it inflated
correctly. As the astronaut ascends towards the surface, the air inside the suit expands
and tries to overinflate the suit, so some of the air is released. In this way, the suit
always stays inflated just as it would be in space.
After a couple hours of training, the divers move one of the astronauts over to the platform
and remove her glove. This training exercise simulates a suit failure, and it’s one of
the things that astronauts practice underwater. The continuous flow of bubbles from the sleeve
shows the regulator in the suit attempting to maintain positive pressure.
Soon, the astronaut is lifted from the water after a successful training mission.
Tim and I head back to the surface too.
That is the coolest swimming pool ever!
Later, I have the opportunity to meet Ron Garan, a real astronaut. He has spent nearly
half a year in space, and more than 27 hours spacewalking. So you know what I had to ask
him.
JONATHAN: You gotta tell me what it’s like to be in space.
RON: What's it like to be in space? Well, it’s a lot like being in the pool here….the
only difference is, when you turn upside down in the pool, you feel upside down. When you
turn upside-down in space, there is no upside down, so you don't have that sensation of
blood rushing to your head. And you can't beat the view.
JONATHAN: Yeah, I guess that's true, huh? What did you do here, that helped you as an
astronaut?
RON: Well, what we do here is we train for our space walks. There's two ways to look
at it. When we were flying the shuttle, we had very specific, very choreographed space
walks. And so for every hour that we spent outside in the vaccum of space, we spent about
7 hours underwater, making sure that we knew exactly how things were going to be. There's
a full scale mockup as you guys saw of the space station down there. So just to know
how to get around, know the lay of the land, know how the equipment works. But nowadays,
since we don't have the space shuttles, what we're really traning for is if something breaks.
If we have a piece of equipment that breaks, then we have to go out, sometimes in a fairly
expeditious manner, to fix the equipment. And we never know what's going to break beforehand,
so we have to kind of train a skill set to learn the basic skills on how to fix anything
that can go wrong outside.
I spend an hour chatting with Ron about being an astronaut, and training underwater in the
Neutral Buoyancy Lab. I explain that I'm a perfect choice to join the space program,
I mean after all, I'm already good at working in zero gravity. But I don't think he was
convinced. So, instead of joining the space program, the Blue World team ended our exciting
day by getting our picture taken with Ron. Sometimes my adventures in the Blue World
take me to fascinating places I'll never forget.