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there's a very significant chapter in
the long history of the hubble space
telescope that I had never found written
up anywhere you could find a few
scholarly tones about all the
bureaucratic warfare from the early
1960s to the mid late 1970s that led to
Hubble actually being approved and
funded by Congress and starting to get
built you could find a lot on the other
end of the story about all the
magnificent images and astronomical
discoveries but oh my god they
discovered the mirror was flawed but
thank heavens they fixed it on we go to
the glorious pictures none of that is
false but it leaves a bit out about oh
thank heavens they fixed it there's not
a space telescope aisle in any hardware
store we just easily go by and pick up
the tools that you're going to need
three hundred miles above the earth
whizzing around at 17,500 miles an hour
with the repairs being done by people
who are wearing the equivalent of double
snowmobile suits triple mittens and
buckets on their head so somewhere along
the way in that gap that hasn't been
written about some people needed to
apply an awful lot of foresight and then
invention and creativity and careful
engineering to actually imagine how do
you do that and then what gear and
gadgets do you actually need to go do it
in orbit and how does that need to be
adapted well that work and in particular
it's a bit about making sure you
actually have the gear and equipment
that makes this prospect of maintenance
of reality that work got done in a
five-year block of time from 1985 to
1990 I worked alongside those engineers
unsung engineers from the Lockheed
Martin corporation in different parts of
NASA they are to Hubble what the hidden
figures computer ladies are to the John
Glenn and early Mercury story the people
whose work is absolutely indispensable
to how it all came out right but whose
names have essentially never been
mentioned and stories of how they came
to be clever enough to do that never
told so filling in this missing chapter
of history so that people could
appreciate the role that engineering
foresight and invent
this and focus on maintenance those
three things play a huge role and why
Hubble is there twice its lifetime
success than it is so let's actually go
back six years before that to your first
spaceflight and what's it like to wake
up in space you know most of us I think
we're awake and rousing about a bit
before Mission Control Center officially
was allowed to start communicating with
us again and you'd hear there's a
distinctive tone that would signal
there's a radio link opening up and then
they just start some music running kind
of like your alarm clock waking up
gracefully in the morning and when they
finished they the voice would come up
the loop usually saying something
innocent like a challenge and good
morning Houston's standing by and then
they leave you to go about your coffee
and your rest if your wake-up ritual
unless something was really very
impressive how does this space compare
with the amount of crew space there was
on a shuttle Oh vastly larger this stage
is a closer comparison but three stories
of it two decks there's two decks and I
mean only a maintenance so it's a pretty
intimate Sauveur space cozy except you
know it's not it is two floors but you
know you've got a lot more room in it
because you don't have to have your feet
on the floor so if this is feeling a
little crowded we'll just put you up
there right but you actually go to go
outside which is something that I've um
tell us a little bit about that
spacewalk you were working on refueling
uh a satellite yeah the shuttle was
advertised as being able to put you
launch carry things in orbit but also
either retrieve them or repair them in
orbit or refuel them and so we got the
assignment that was focused on well
let's prove you can actually refuel the
easy part was you know can you make two
couplings that will go together and let
liquid go back and forth the tricky bit
was the propellant the fuel that all
satellites pretty well all satellites
maneuver with is super toxic and super
explosive no one who owns a satellite is
going to consider us a credible
refueling service if we've never
actually done refueling with this real
nasty propellant that's what a hydrazine
a hydrazine so for one thing if you
squeeze more hydrazine into a tank that
already has some in it if you do that
too quickly you know raising the
pressure and the tank raises the
temperature in the tank
and there's a really rather low
temperature that if you push hydrazine
to that temperature it will just
spontaneously explode with no added help
so you've got to have your
thermodynamics right and you've got to
have good control over how quickly
you're adding new hydrazine in and this
experiment let us do some of that
thermodynamics experiments and then the
other thing is because it's so toxic and
so nasty do you really have the
equipment that will let astronauts open
up a fuel tank that's already got
hydrazine in it put a fuel line in that
also has hydrazine in it and be
confident they won't get contaminated on
their suits or if you get tamanna on the
outside of a spacesuit you're safely
sealed inside but you've come back into
an airlock and some of that stuff on the
outside and yuri pressurized the airlock
all the little hydrazine frost on the
outside of your suit will go into the
vapor in the air I mean about a
fingernails worth of hydrazine ice if it
circulated back into the shuttles cabin
it was reckoned would at least sicken
everyone and possibly be more dangerous
than that the challenge was I want you
to refill the gas tank on your car
without ever touching the gas tank the
clever engineering problem we had to
solve for that was how do you make a
gadget that will let you do that
absolutely terrified so you took you
three and a half hours yes you're
working yeah we were the partner yes it
was a which is quite short by spacewalk
standards actually but that was the
confines of our test and then there was
a fairly minor problem with one of the
space shuttle's antennas that we need to
do needed to do a bit of an adjustment
to as well all flights are great flights
you want to fly as soon as possible as
long as possible high inclination to see
as much of the earth as possible and
rule number five is get a spacewalk if
you possibly can and only a quarter to a
third of of people who become astronauts
actually ever end up outside on the
spacewalk I mean you get to put on your
very own body shaped spaceship your
pilot in command of your own spaceship
move around and the flexibility of
zero-gravity not in a water tank where
you can simulate it pretty well but
actually with the planet going by right
up there and then have always pretty
fascinating challenging and fascinating
work to do it's a very coveted thing to
get to do if you're the kind of people
we are
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