As much fun
as it is just to go to space, being able to go outside your spacecraft
is even more exciting. But before you can float out the door into
space, you must spend many hours learning how to do a spacewalk,
or extravehicular activity (EVA).
astronaut trains in the Neutral Buoyancy Laboratory, or
NBL, at the Johnson Space Center, Houston, Texas.|
must learn how to put on your 127-kilogram (280-pound) spacesuit
-- it will provide you with the air you need to breathe while you're
outside your spacecraft. It will also keep your body at a comfortable
temperature even though it may be 200 degrees below zero to 200
degrees above zero outside.
Because the suit
is so large, you must practice moving around while wearing it and
learn how to use tools with bulky gloves on your hands. Both astronauts
and cosmonauts practice doing spacewalks in large pools -- astronauts
usually spend seven hours training underwater for every hour they
will spend spacewalking during a mission.
have a pool at the Gagarin Cosmonaut Training Center in Star City,
Russia, where cosmonauts and astronauts learn how to use Russian
spacesuits. Cosmonauts and astronauts train to use U.S. spacesuits
in the Neutral Buoyancy Laboratory at the Johnson Space Center in Houston, Texas.
The NBL, as
it's called, is a huge pool filled with 22.7 million liters (6.2
million gallons) of water. In fact, it's the world's largest indoor
pool -- 62 meters (202 feet) long, 31 meters (102 feet) wide and
12 meters (40 feet) deep. At the bottom of the NBL sits a model
of the International Space Station, which is the same size as the
one orbiting the Earth -- that's why the NBL needs to be so big.
There is also a model of the space shuttle's payload bay.
in a pool is similar to being in space, but not quite the same.
You're not truly weightless like in space, but are what is called
neutrally buoyant. The term neutrally buoyant means an object doesn't
want to float to the surface or sink to the bottom. Scuba divers
try to be neutrally buoyant so they don't sink or float upwards
when they're underwater. In the NBL, weights or floats will be attached
to your spacesuit to make you neutrally buoyant. This makes you
feel much like you will in space, when you're floating free without
You will begin
your training by going through your planned spacewalks while wearing
standard scuba gear. Once you've gotten comfortable with all your
assigned tasks, you will be start practicing them while wearing your
spacesuit. In the pool, scuba divers will help you move around until
you get used to moving in your spacesuit. They're also there to protect
you in case you have a problem with your suit. You'll also learn how
to stay in one place -- don't push too hard in space or you'll float
crane lowers Expedition 1 Commander Bill Shepherd into
at the Gagarin Astronaut Training Center in Star City,
learn how to use all the tools you'll need during your spacewalk.
If you're going to help build the International Space Station or
work on the Hubble Space Telescope, you will practice only the specific
tasks you will do in space. You will practice every task dozens
of times before you ever leave the Earth, until you can do it correctly
every time. If you're going to be part of a space station Expedition
crew, you will learn how to do many tasks outside the space station,
so you'll be ready to fix anything that might break.
By the time
you're ready to fly into space, you will have spent more than 100
hours underwater practicing for your spacewalks. When the time comes
to put on your suit and float out the door into the vacuum of space
for the very first time, you'll know you're ready.
And while you're
outside, don't forget to take some time to enjoy the view. You will
remember that first view of the Earth through your helmet faceplate
for the rest of your life.