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Astronauts in Hard Hats
Outer space is a heck of a place to build a home. Just ask
the astronauts charged with assembling the International
Space Station. For starters, it's alternately frigidly cold
and dark as ink, then blisteringly hot and bright as a
noontime desert—a climatic flip-flop that takes place
every three-quarters of an hour. Below, see and hear six
astronauts tell what it's like to "translate" (spacewalk)
and otherwise cope with the largest construction project
ever undertaken in orbit. For capsule biographies of the
astronauts, click on their names.
Working in space
"Building the space station is not an ordinary construction
job. It's very different, and it's different from building a
house or a skyscraper, in that we're working in a very hostile
environment, a very isolated environment. So, first of all,
we're not as efficient working in these big, bulky spacesuits.
We're time-constrained, up to eight hours at a time. We're
constrained on the amount of tools and weight we can carry to
space. So there it's somewhat unique.
"But part of the problem is,
we have to have it all figured out before we show up in
space.
It's got to be all figured out, while on a construction site,
if you're building a house and you cut a two-by-four to a
certain length and you go to install it and it doesn't work,
well, it might be a little inefficient, but basically you toss
that board, you go cut another one, and you're off and
running. If we show up in space, and now that piece that we're
putting on doesn't fit, we're out of luck. That may have just
delayed the next series of missions. We may have to add
another mission now to bring up the right component, because
they're all linked. So it's very complicated." -Kent Rominger
"When you go up there for construction,
not only do you have to bring the material to do the
construction and all the equipment to do the outfitting, but
you have to bring every single little tool that you might
require, every infrastructure that you require to build the
actual station. And then you have to bring every single thing
you need to sustain the lives of the construction workers, the
crew members, that go up there, because there is absolutely
nothing. As I often say to people, unfortunately,
there is no hardware store around the corner, so if you
forgot a particular type of washer or you don't have the right
screwdriver, well, you can't go back and get it." -Julie Payette
"The tasks themselves are actually
rather mundane. Although the environment is rather exciting,
we were hooking up power and data cables between Zarya, the
Russian control module, and Unity, the American-built node. So
we were hooking up data cables, power cables, we were putting
out sun shades, cleaning things up, preparing for the next
missions. So on some level, the tasks are the mundane tasks
that go into building something—to making a laboratory,
an office building, ready for people to inhabit it and do work
in it.
"That's what's fascinating about it.
It is the environment in the end which is the challenge
and not the mundane tasks. It's being able to go outside and
to have only two people at a time typically, and to work in a
vacuum with temperature extremes from -200°F to
+200°F, and [going] from daylight, and 45 minutes later
it's dark, 45 minutes later it's day." -Jim Newman
"There is a plan as the space station
grows to take up a large space station manipulator arm, and
once it is on the station, that will be able to help us with
the construction....This new space station arm is able to walk, it can literally walk from one end to another. The beauty
of that is that, as the station grows and becomes very large,
you'd have a hard time designing any arm to do everything you
wanted it to do. So what's been designed into the station is,
either end of the arm can attach itself to any point on the
station. So ideally you attach to an area where you need to
work, and if a week later or days later you need to work in
another area of the station, you can walk the arm around the
station to position it to a more usable space to work." -Kent Rominger
Spacewalking
"What we call 'translating' around the space station, people
call spacewalking. But, of course, you can't actually walk in
space. There's nothing for your feet to walk on, in the sense
of gravity holding you down to walk.
What we end up doing is actually more of a space crawl.
It's like climbing something that's going straight up. That
is, you use your hands a lot, in fact, almost entirely, in
order to move around the space station. So you grab ahold of
one handrail, then you grab ahold of the next one. You let go
of the last one, you grab the one you're on, you grab the next
one. And that's literally how you do it, from one after the
other handrail to wherever it is you're going.
"There is one other way, and we call it the Elevator. That is,
if you get on the end of the robotic manipulator system, on
the end of the arm, it can actually take you wherever it is
you need to go." -Jim Newman
"One of the things we have to do while
we're on our spacewalks is loosen a lot of bolts. And that's
complicated in space because you have to react to all the
torques. That's the technical way to put it, but if you've
ever been in a swimming pool and worked on something, you know
that if you turn something one way, it's going to turn you the
other. If you're on ice and you push on something, you
obviously go the other way, and in space, of course, that's
true in all three dimensions.
"So if you have an electric drill as we did, and loosen a
bolt, and you're not tied down with your feet or your hands,
you can feel it trying to turn you the other way. So we
have to react to all the torques ourselves, and there are two
ways to do it: one with your feet in a foot restraint, or
free-floating." -Jim Newman
"[A] lot of the tasks we have to do
free-float. You're really working hard. You might watch an EVA
[Extra Vehicular Activity, or spacewalk] and think, "Gosh,
these guys are moving slow, and they're not working that
hard." Inside the suit,
you're constantly flexing all of your muscles to keep
control. A good example: If you start translating [spacewalking],
and then you go to stop—you put on the brakes with your
hand—you're going to pitch up. Your feet are going to
tend to fly up over your head. So you have to constantly sense
any rates that your body might be getting on it, then put in a
force to null that rate. So when you go to stop, you're
stopping with one hand and you're pushing up with the other,
so you don't pitch out of control." -Mike Gernhardt
Inside a spacesuit
"Training in the Neutral Buoyancy Lab [a swimming pool used
for instruction before spaceflight] is very good training.
It's harder in some ways than actually going outside, because
of the gravity effects in the pool. Once we're in the pool,
they put us in a spacesuit, a real spacesuit, and pressurize
us ... and that's what really makes a lot of spacewalking
difficult, because your hands are in this balloon. And you
know that if you want to bend a balloon, it takes work. So
every time you close your fingers or open your hands, you're
actually working against the suit...The training in the tank
is very important because it doesn't pay to fight the suit.
The suit will win, so
you have to learn how to be one with the suit." -Jim Newman
"Different tasks can be more tiring than
others. But just the entire experience of being in the suit,
which is pressurized, can be very, very tiring, because any
movements—you're sort of like the Michelin Man, you
know, you're puffed up in this suit, which means that any
movements you make with your hands or your arms, they're all
against pressure. It's like, you're pressurized, and you're a
little puffed up, so there's a lot of resistance.
"The way the suit is designed, it's very protective, because,
of course, you don't have anything out there.
You're in your own little spacecraft, actually, when
you're wearing this suit. So as a result of all the
protections, it's kind of stiff. So essentially what they're
doing is lifting weights for six to seven hours. And so
obviously if the task is very intensive with their hands, then
they're lifting even more weight. So there are times built in
for them to rest. But from an endurance and a strength
standpoint, it's an incredible workout." -Pam Melroy
"The American suits will have a SAFER
backpack on. It's called a Simplified Aid for EVA Rescue, and
it's a fancy acronym for saying that if for some reason your
two tethers have come loose and the worst has happened and
you've floated away from where you've been attached to the
station, you can activate this SAFER, and it's got some
nitrogen jets that you can use to fly yourself back to the
station and grab hold and get yourself retethered." -Rick Husband
"If we got a small hole [in our
spacesuit], our oxygen would start coming out of the
spacesuit, and the pressure would start to drop. If the
pressure drops too far, then you'll get the bends, and if it
drops below about 2.5 psi, then you don't have enough oxygen
to maintain useful consciousness.
"Now, we have a device called the Secondary Oxygen Pack on the
back of our backpack, and it's got a whole lot of oxygen in
it, and it would be able to support a small leak
for—depends on how small it is—but for at least 30
minutes. So for a small leak, we'd have our secondary-oxygen
system kick in, and we'd be heading back to the airlock and
repressurizing, and we'd be fine. A big leak—like
a big hole in the suit, say a half-inch hole or something like
that, or if your glove blew off—would pretty much be a real bad day for you." -Mike Gernhardt
Better be tethered
"Your safety tether is like a reel. It's a wire tether on a
spring-loaded spool that tends it, and that is attached to you
and the space station at all times, because if you should ever
let go of the station, the tether will pull you back in, or
you can grab it and pull yourself back in. If you didn't have
that tether and you let go,
even if you're two inches away from the station, you can't
swim over there. There's no water to create forces against. So it's critical
from a safety perspective that you be tethered at all times."
-Mike Gernhardt
"It is a challenge, because if you let
go of something, it floats away. So you have to be very
careful in how you tether.
If you let go of the structure, you would
float away, so you have to be very careful, make sure your safety
tethers are secure." -Jim Newman
"One of the things that you learn to
do, in addition to processing the task that you're working on
and thinking two or three steps ahead,
you're also constantly thinking about where your tether
is, where your buddy is, where his tether is, and where the
airlock is. So that in any point in time, if something should
go wrong, if he should get a leak in his suit, I know where he
is, and I'm going over there, and I'm going to help him get
back to the airlock." -Mike Gernhardt
Blueprint for a Space Station
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Astronauts in Hard Hats
Inspired by Science Fiction
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Free-Falling
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| Updated November 2000
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