All language subtitles for How To Build A Satellite

It must be right first time.

You can't service it
or bring it back

or complain to the manufacturer
that it doesn't work.

Failure in space is not an option.
If something goes wrong,

customers are not happy and they
don't come back to you again.

So what we've got here

is the startings of
a telecommunications satellite.

We've got seven smaller thrusters
and we have a main engine,

which is fitted inside the cone.

If we sent a spacecraft
up into space with no insulation,

the distortions caused by
the very temperature differences

would buckle the structure
and destroy it.

If the heart stops,
the patient dies.

If the quartz crystal stops
oscillating, the satellite will die.

If I say I work on satellites...

"What, you put the dishes
on the walls, do you?"

They just don't...
They don't understand

that there's something up there
as well, in space.

The moments leading up to the firing
of that main engine is very tense.

It's the nearest we get
to science fiction.

It's just something people dream of.
We sort of live a little bit
of that dream.

Space is incredibly special. What
we do is quite exceptional here.

After almost two years
of precision engineering

and costing over £100 million,

a six-tonne
telecommunications satellite

is sitting on top of this rocket.

In terms of the satellite,

the risk here of course is that
it's now about to be shaken

from the rocket motors.

It's also going to get
a fantastic thrust load on it.

And now it's just one day away
from being fired into orbit.

The amount of testing that we do
to verify it effectively

never guarantees you 100% but
it guarantees you that you've got

a very, very high probability of
success and that's what we go for.

The violence of the launch
is the most dangerous moment

of a satellite's life.

We have to make sure
it survives this phase

and then it can go into operation.

This is the bit where
we all get that, er...

A little bit of butterflies
in the stomach.

And although it's being
launched in faraway French Guiana,

most of it was designed
and built in Britain.

We're on the A1 heading south
at the moment.

It's about quarter to eight
in the morning.

I've done this trip
for the last 30 years.

Bob Graham is a site director
at Astrium,

one of the biggest spacecraft
manufacturers in the world.

If people say,
"Who do you work for?"

and I mention the name
of the company

there's often a slightly quizzical
look on their face.

Then it becomes quite a surprise
when you say,

"Well, I work
in the space industry."

When the Space Race
was at its height in the 1960s,

the United Kingdom had virtually
no space industry.

Today, British engineers lead
the world in satellite design

and manufacture.

Working in space is always
something different

and there's not many people
in the industry.

So in the pub when someone says,
"What do you do for a living?"

You say,
"I work in the space industry,"

they do give you a funny look.

We watched the moon landings

and everything that NASA did
was quite incredible.

For me, I can't quite believe
I'm being able to do this.

Yeah, we've known each other
a long time.

26 years? Haven't we?

Is it that long?

I think so. God. Yeah. Oh, dear.

We don't look that old either,
do we?

What's Mr Cross up to?
You visitors are all the same!

Astrium have factories
all across Europe

but employ around 3,500 people
in the UK.

Every satellite the company builds
starts life here

just outside London
on their site in Stevenage.

I've worked here
for nearly 30 years.

I came to Stevenage in 1982
for what was sold to me

as a 12-18 month position
and I've been here ever since.

It gets into your blood.

It's a really,
really good job to have.

There's not many areas
within in the country

where you can actually work
on spacecraft.

Telecommunication satellites are an
integral part of the modern world.

They allow us to send television
pictures and communicate

over vast distances using all
of today's modern technology.

But because they operate
in deep space,

they have to incorporate some
extremely complex engineering.

A modern communications satellite
needs to be capable of surviving

the possible impact of debris

travelling at thousands of metres
per second.

And they need to be able to operate
in temperatures that fluctuate

between minus 200 degrees
Centigrade

to a blistering 150 degrees
Centigrade.

And yet, the satellite
has to continuously operate

for a guaranteed 15 years,
because out in space,

there's absolutely
no prospect of repair.

I think people do
take it for granted.

So if you pick up your mobile
phone to make a phone call

you don't realise it's bouncing off
a satellite. Or you turn on your TV.

It's just stuff you do everyday
without thinking about it.

The upper quadrant,
section five... Yeah? ..looked fine.

A modern telecommunications
satellite

can be over five metres high
and three metres wide.

Although astonishingly complicated,

there are basically two distinct
parts forming its main body.

The mechanics...

and the electronics.

The mechanics make up
what's called the service module.

And the electronics make up
the communications module.

The satellite's central skeleton is
built around a carbon fibre cylinder

connected to aluminium panels
which hold four fuel tanks,

a main engine,
thrusters and batteries.

This is the service module.

On top of it
sits the communications module

which carries the satellite's
complex electronic payload.

Also added are solar arrays.

Attached to the main body,
they capture sunlight

which is converted into electric
power, and antenna dishes

that will transmit and receive
signals from Earth.

And by looking at different stages
of the build

it's possible to understand
how they're put together.

From the manufacturing viewpoint

this is the beginning
of the process.

The build begins with a central
core, the skeleton of the satellite.

Strands of carbon fibre
coated with resin

are wound into a complex pattern
to make the cylinder

as strong and light as possible.

When it's finished
and vertical it weighs just 20kg

and is ready for the next
stage of construction.

In here is where we produce
our panels, our honeycomb panels.

Aluminium skins. Very, very thin
skins, very lightweight.

Low mass is key in terms of space

and we use aluminium
because it's good structurally.

The aluminium panels are attached
to the central cylinder

forming more of the basic structure.

John Richards
has been building these

for almost his whole working life.

We're just putting the flight
bolts into the SM floor

and that attaches the floors
to the central structure.

I'm not sure how many bolts,
probably about 20 in each quadrant.

I don't suppose, really, people
just think of satellites

as something that's up in space
orbiting round.

I don't suppose
they think of actually what
goes into building them.

You take your time,
because as you're probably aware

that these things are worth
a lot of money.

And it only takes us
to make one slight mistake

and it could end up
costing millions of pounds.

Best thing about working here
is the people like John and people
that have been here years,

always willing to pass on experience
and to help you out.

After the basic structure
is finished

the rest of the systems
can be added.

Once I've gone through my final
testing we have a big clean down,

make sure it's particle free,
ready to be accepted

into Mick's area and I'll give him
a shout and usually that's it.

I mean it's very casual, it's just,
"When you going to be ready?"

"Tomorrow", whatever,
and just hand it over to him.

Satellites have to be built
in extremely clean environments

because any dirt inside the moving
parts can have devastating effects

once they're in space.

In fact there are special areas of
the factory that actually have fewer

dust particles than you'd find in a
typical hospital operating theatre.

And in here, engineer Graham Viney
and team leader Mick Atkinson

have the tricky task of managing
the assembly and integration

of the fuel tanks, the pipe work and
the engines of the service module.

We do get problems now and again
because when it's designed,

it's all done on a model
and then when it comes down to us

it is quite a bit different in
the real life, putting it together.

There's certain things that we know
we can't do in the design

because it just won't be able
to be done on the shop floor.

So what we've got here
is the overall service module

or the startings of the service
module of the telecommunications
satellite.

What you can see are two tanks
of an eventual four tank
propellant system.

On the outside,
in several locations,
we've got seven smaller thrusters

and we have a main engine,
a liquid apogee engine,

which is fitted inside the cone.

The service module carries
four fuel tanks,

all placed around the central core.

Each fuel tank can withstand
an internal pressure equal

to being over 200 metres underwater.

The fuel is used
for the satellite's engines.

The main engine fires the satellite
out into orbit after it's launched

and then, for the rest of its
lifespan, the other seven pairs

of smaller thrusters will keep
the satellite in its orbit.

The fuel for all of these engines
is delivered

by one of the most explosive
mixtures known to man -

Nitrogen Tetroxide and Monomethyl
Hydrozene, or NTO and MMH.

As you can guess from the names,
these aren't particularly

pleasant liquids, so extremely
toxic and extremely hazardous.

If you take in any
of the NTO or the MMH,

basically you will suffer
from burns, internal burning

and then eventually it leads
to death. They are lethal.

The reason for choosing these
dangerous fuels is simple -

their explosive quality.

The more explosive the mixture,
the bigger the thrust,

and the less fuel you need.

But at three tonnes,
this volatile mixture is still half
the satellite's launch weight.

And with such an explosive power,
the tanks need to be tested
to destruction

to ensure they'll
survive the trip into space.

Part of the testing
of the propellant tanks

is to take it to an actual
burst pressure.

We don't test it with gas,
we tend to test it with water.

We increase the pressure
and we get up towards 49 bar

and the tank will split.

Although the tanks
won't be filled with fuel

until just before the launch, it's
still delicate work fitting them.

We're just about to install
the third propellant tank

into the structure.

Two are already installed,
this is the third one.

It is quite tricky, yeah.
And it's worth a lot of money,

of course, as well. About the price
of a good house, actually, yeah.

The propellant tanks
are built from titanium

because the metal doesn't react
with the fuel in any way.

And they are machined
to be wafer thin.

'We've got to be so careful
that no damage occurs

'during this process,
so it's quite delicate.

'It never goes wrong. It can't.
It can't go wrong.'

LAUGHS

'Yeah, it's quite a big operation
in the tasks that we perform'

so it's good to get it
out of the way.

We've got it off to a T now.

Hopefully, tomorrow we'll be
putting the other tank in.

It's the end of a successful day,
and so, with the tanks fitted,

the next stage of the build
will be adding the engines.

So when I tell people I work in the
space industry,

it either sparks conversation
and genuine interest

or is a complete
conversation killer.

The concept of satellites came
from Arthur C Clarke back in 1945.

He thought, "How can we transmit
data from one side of the Earth

"to the other side of the Earth?"

These things will make possible
a world in which

we can be in instant contact with
each other, wherever we may be.

'Men will no longer commute,
they will communicate.'

With the launch of Telstar in 1962,
transmitting sound and vision

across continents and oceans
became a reality.

'We have acquired the Telstar,
Captain Booth puts his thumb up.

'And there is the picture
direct from Telstar.

'This is the sort of image

'and the sort of sound
on which, in fact, the future

'of inter-continental
telecommunications

'via space vehicles is built.'

If you threw something
at the horizon

it would just fall and drop.

If you threw it hard enough,
you could probably throw it

past the horizon,
and where would it drop to?

Well, it would continuously drop.

And that's what we're talking about.
When you have enough energy

to throw a rock or whatever it is
to the horizon

but you throw it hard enough that it
then continuously falls,

then you're in orbit.

For a satellite to stay in the same
place in the sky

it has to travel at the same
rate as the Earth spins -

once every 24 hours.

This is called geostationary orbit

and it can only be achieved
at 35,786km above the equator.

Any closer to the Earth
and the satellite orbits too fast.

Any further away and it's too slow.

And that's why, in the UK,

all TV dishes point at 29 degrees
above the horizon.

They are all receiving a signal
from one particular satellite

that never moves in relation
to our homes.

Microwaves won't work round
the curvature of the Earth.

You need to be able to see the point

that you're transmitting to
or receiving from.

The satellite receives and transmits
signals through large antenna dishes

that fold out from its main body.

But they're very different from
the dishes we see outside our homes.

They have carbon fibre skins bonded
onto a Kevlar honeycomb core,

but there's another,
more important difference -

they don't have a smooth surface.

The customers will specify
a coverage. That coverage will be

to maximise access to
the population and the service area.

So for the one we're looking at here,

which is over Europe, we're
looking at the landmass of Europe,

so the more we can do to suppress
the unwanted power over the sea,

the more we can put it where they're
going to get their revenue from.

What we see in the top-right corner
is what we're actually doing
to the reflector.

We're slowly manipulating
the reflector surface, very subtly -

in tens of millimetres -
to actually produce a
highly-concentrated area over Europe.

Shaping the reflectors in this way
focuses the signal better,

and this is critical,

because the power they transmit back
to Earth is astonishingly small.

The power that we're transmitting
for each channel

is equivalent to a 100-watt light
bulb, and that 100-watt light bulb

is 22,000 miles away
from the surface of the Earth.

This is quite amazing
technology, really.

The satellite
is kept in its correct orbit

with a series
of different-sized engines,

but given it weighs around
six tonnes, it doesn't need
the engines you may think.

If you were to fit this engine
to your car, you'd have trouble

fitting in
the three tonnes of propellant,

but you may move it very, very
slowly. It's not going to take off.

But we're in space,

so we can use this engine on
a six-tonne satellite and move it

through space
because there's no friction,
so it's relatively easy to do.

Once in geostationary orbit,
the smaller thrusters will take over

from the main engine to keep
the satellite in position.

We have thrusters dotted around
so that we can control

the attitude of the satellite,
to keep the antennas pointed,
to keep the data flowing.

We've got influences from the Earth,
which is not a perfect sphere,

so gravity will have an effect,
and solar radiation from the sun.

We have large solar arrays that will
pick up from the solar radiation

and slowly change
the attitude of the satellite

and we need to fire a thruster
to bring it back.

These manoeuvres happen regularly,

just to keep the satellite
in its correct position.

But at the end of its life,
these small thrusters will use

the last of the fuel to blast it
even further away from the Earth

and into a graveyard orbit, which
will be its final resting place.

Whilst all the structural components
for the satellite are built
in Stevenage,

the communications module
is built in the company's
other UK site at Portsmouth.

Portsmouth's history
is well-known,

of course, for the maritime aspects
of Portsmouth, but actually,

for a long time,
maybe associated with that

there's been a capability

in defence electronics.

More than 50 years
this site has been here,
and over the last 20 years

we've seen this shift
from defence electronics to space.

It's here that
the electronic components

that form the communications module
are made and fitted.

I don't think we talk about the
space activities very much here.

I don't know whether
it was because it started off

being defence-oriented
and therefore quite secret,

and whether that's
sort of part of the culture.

But nevertheless,
people in this area
don't normally associate it -

even the ones that live here -
don't know that we make
sophisticated satellites.

Over 12 months, thousands of
individual electronic components

will be designed,
built and fitted to the structure.

And their reliability is critical.

Failure in space is not an option.

Customers spend 150 million
buying a satellite and if something

goes wrong they are not happy and
they don't come back to you again.

This communication module is also
known as the "payload".

On a spacecraft
there are many parts,

but essentially it
comes down to the payload -

the reason for it being there,

what it wishes to receive
and what it wishes to transmit.

Each satellite is
guaranteed by the company

to work for at least 15 years.

If it doesn't, they don't get paid,
so attention to detail is critical.

The main driver for what
we do here is reliability,

so on the site here we have 3,000
engineers - no service engineers.

Once the equipment on the spacecraft
goes into service it has to operate

for 15 years without any reduction
in its quality of service.

During that time,
it gets hot and cold

so the heat on board the spacecraft
makes the electronics grow old.

The radiation gives it sunburn,

so it has to survive through
all those things.

At the heart
of the communications module

are micro-electronic circuits
called "hybrids".

These are computer processors,
like silicon chips,

but are built for space.

The circuits are printed
onto gallium arsenide,

a semiconductor,
and bonded onto a ceramic tile.

Then they're connected
with gold wire.

I'm placing a one-thou gold wire
onto a substrate

using a combination of heat,
pressure and vibration.

Each satellite is made up
of around 20kg of pure gold.

It's 99.9% pure gold,

so, yeah, it's good stuff!

Only the best!

Pure gold is stable, doesn't degrade

and is an excellent conductor
of both heat and electricity.

I was only 18
when I first did wire bonding

so I suppose
I was quite adaptable to it.

Even though I've got chubby fingers,
I like doing delicate work.

I haven't tried embroidery yet,
though!

Once complete,
the chips are incorporated
into bigger electronic units.

I've been working on this
for the best part of four years,

to actually get it
from the early design,

right through to actually realising
some of the hardware.

Decoding commands -

it's a bit like you sort of pick up
your telephone and dial a number.

This particular unit, crudely, it's
doing the same sort of function.

Then the components are tested
again and again and again.

We've got about 8,000 test steps
on this particular unit on its own,

so end to end, it's probably
something like around
two to three months, I would think.

But certainly on the design side,
you know, you're very conscious

that this, actually, is going
to be up there for 15 years.

That's quite at the fore of your
mind in terms of everything you do.

It certainly is in my mind, anyway!

But not all the components
inside the satellite
rely on modern technology.

I've worked in this building
for about 12 years,

but I've been engaged on crystal
growth for the last 42 years.

Morning, Mike. Morning.
A huge problem for satellite
communication is interference.

This happens
when the outgoing signal is confused
with the incoming signal.

This problem can be prevented
by quartz crystals

built into devices
called "resonators".

You can look on the quartz
resonator as the beating heart.

If the heart stops, the patient dies,

and similarly, with a satellite,

if the quartz crystal stops
oscillating, the satellite will die.

Oscillating crystals are used
to control all the frequencies
the satellite transmits.

And the quality of the crystal
is critical

because if there's any impurity,
they won't work.

This is a block of natural quartz
that we purchased
from a small company

that uses quartz for crystal balls.

Something like that
would set you back somewhere between
£10,000-£20,000.

OK, Mike, bring in the crane.
Because Derek needs to ensure
the crystal quality and supply,

he originally
used purchased crystals

to provide seeds
from which he grows his own.

What we're trying to do here
is to replicate the way

natural quartz grows in nature.

Natural quartz will grow deep
in the Earth's crust. The difference

is we're trying to speed up
the process so we can complete

the growth in, essentially,
a few months rather than
a few thousand years.

Over the next three months,
under a high temperature

and enormous pressure,
crystals slowly form
in a solution of caustic soda.

We've been producing them
for 25 years or so,

and so far nobody has beaten them.

Once they're formed, the pure
crystals are first sliced...

..then shaped...

..and finally polished

until they are little bigger
than a contact lens

before being incorporated into
the satellite's electronics.

Our crystals are the purest
in the world.

I can say that
with absolute certainty.

Once all the electronic sections
have been made,

they need to undergo a series
of tests before being attached

to the communications module.

My name's Gary Stancombe.
I've worked in vibration tests

and mechanical tests
at Astrium for 15 years now.

I'm going to do some taping down to
tidy it up and then we'll be ready.

OK.

This test is to check they will
survive the extreme physical impact
of the satellite's launch.

What we're doing today is we're
going to subject this unit

to a sequence of vibration tests
to simulate the launch environment

when the rocket lifts off
and those eight minutes
which will take it into space.

It does get a fair old shake.
Today, we're going to subject it
to a 20G vibration test -

20 times gravity. So anything
in there will feel 20 times heavier.

Every electronic component
is tested in this way,

sometimes to breaking point.

It is a hard test, yeah.
It's a thorough test.

It has to be.
We have to ensure that everything

is going to still be working
once the unit gets into space.

We do see failures,
but not too often.

But it's not just the vibration
of the launch that each component
has to cope with.

There are also massive shock waves.

These happen as explosive charges
decouple each stage of the rocket.

From the solid boosters,
the satellite housing

and main engine, through to the
deployment of the satellite itself.

These are quite substantial shock
waves so they need to be tested.

OK, and that's the shock test!

Once the electronics have
survived all these tests

they can be fitted
into the communications module.

Ian Kilby started work
as a technician over a decade ago,

but he's now in charge of ensuring
everything is connected correctly.

When I moved up from technician
to engineer, at that point

you're no longer allowed to fit
any equipment to the payload.

I do miss the hands-on
side of things.

I used to enjoy
the challenges that wave-guide

and co-ax present to the fitters,

and yeah,

sometimes I do wish,
on particularly bad days,
I wish I was back down there

on the tools and could not worry
so much about things.

At the moment, the communications
module is in two pieces

and Ian has a brave attempt at
explaining how it all fits together.

Basically the signal,
when it's received from Earth -

when the whole satellite's coupled -

there'll be an antenna,
a receiver antenna on the top floor.

The signal will come in.
It goes through the equipment
on the top floor.

They amplify it,
clean up the signal,

get the part of the signal
we require.

It then travels down, down through
the payload and there will be

some equipment called MPMs
which are not installed yet.

It travels up through the switch
network, goes up through the OMUX,

it's amplified again
and harmonised a little bit more,
the signal is cleaned

a little bit more again
at the OMUX level,
and then basically, it comes back

to the top floor, to a feed-horn, to
the reflector and then back to Earth.

Ian's idiots' guide to a payload!

Modern telecom satellites can now
transmit over 300 digital channels
simultaneously.

But just 20 years ago,
they could only cope
with ten analogue TV channels.

And their speed of transmission,
or lack of it,

was apparent to everyone.

THEME MUSIC

If you think back
to Terry Wogan's show, when he used
to have one on BBC One...

..the very first sort of
satellite links, London to New York,

it was almost painful to watch.

She called me, did she?

# I hear you calling me. #

Am I speaking to Linda Gray?
HIS WORDS ECHO: ..Linda Gray.

Yes. Well, that's established
that it's not working.

SHE LAUGHS

With the amount of lag, you had
to wait for the signal to go,

or Terry's voice to reach the USA,
and then the response time back.

It was an eternity.
I'm sure people remember that.

It just took forever.

When we talk on satellite like this,
you know, the miracle of sound,

there's just a little
second or two delay.

So it's not that
Barry's hearing has gone.

It's merely it's a long way
to Los Angeles.

But now with the speed,
the processing power and the speed

of modern satellites, it's barely
noticeable. It's, like I say,
within a second.

Once all the electronic equipment
is fixed, the side panels

and the central structure
are joined together to form
the complete communications module.

These are some of the most
delicate parts of the satellite.

And to safeguard them in
the extreme environment of deep
space, they need special protection.

My name's Katy Smith.

I'm the thermal architect here

and I've been working here
for about six years.

My job is the thermal design, the
build, the test of the spacecraft.

Deep-space environment's
incredibly hostile.

It's incredibly cold -
minus-270 degrees C -

whereas the sun-pointing surface
could be in the region of 150,
if not more.

And on top of that,
you're in a vacuum so there's
no convective environment,

you can't reject heat
like you would.

For example, your cup of tea, when
you blow on it, it removes the heat.
It doesn't exist.

And the satellite needs
to be able to operate within these
massive temperature differences.

If we sent a spacecraft up
into space with no insulation,

it wouldn't work.

You'd have one side with
severe damage to the structure
because of the sun's influence.

You'd have panels dropping off.
So the distortions caused
by the temperature differences

would buckle the structure
and destroy it.

And the heat isn't just a problem
on the outside of the satellite

because these extremes
of temperature could be

disastrous for all the on-board
electronics inside.

They can only operate
between a cold minus-10 degrees

to a warm 40 degrees.

So to keep the internal temperature
within this range,

the satellite is
wrapped in material called Kapton.
Kapton is a high-temperature layer.

It's very robust.
You can use it in an environment
from minus-250 degrees C,

up to a continuous operating
temperature of about 290 degrees C.

I think the best way of describing
it as a home product would be
a Quality Street wrapper.

It's difficult to tear,
incredibly light,

so for a space environment,
it's hugely applicable.

But Kapton can't protect
the satellite on its own.

What you're actually seeing here is
a very thin deposition of aluminium.

So here, when you can see the gold
outer layer, it's not actually gold.

What you're seeing
is the vacuum-deposited aluminium

behind the Kapton, like that,
giving it an amber or gold effect.

The aluminium-backed Kapton forms
a blanket, insulating the satellite

and preventing heat being lost to
deep space, while at the same time

stopping the sun overheating
the electronics inside.

I know it seems
kind of counterintuitive

because you've got large amounts
of energy coming in from the sun,

but to balance it out
and find a happy medium,

you have to block some of the sun,
dump some of the heat

and supply some heat internally.
It's a really complicated
juggling act.

The Kapton blanket is
the first line of defence at keeping

the satellite at
a reasonably constant temperature.

But the electronics inside
also create their own heat,

and this, too,
needs to be dissipated.

To do this,
some very clever engineering

is also incorporated into
the two large structural panels

on the outside
of the service module.

A complex matrix of pipes act
as massive radiators, dumping heat
generated by the electronics

and keeping the internal
temperature constant.

A heat pipe is a very,
very effective method of moving heat
from one local region to another.

There's no working parts,
no electricity required,

so power-wise, it's good.

But unlike household radiators,
these pipes contain ammonia,

because it boils and vaporises
at just the right temperature -

33 degrees centigrade.

So what happens, is at one end,

in the hot, high power
dissipation region,

what will be a liquid
at that stage evaporates.

The vapour then travels up the tube,
up the centre of the tube

to the cold region
and at this region it condenses.

It dumps the heat
and then travels back down

to start the whole cycle again
in the form of a liquid.

There is one final line of defence,

which is also crucial in reflecting
heat away from the satellite.

And it's all down to this team.

I know it sounds very cheesy,

but it's the satisfaction of knowing

that you're actually
contributing to mankind.

You see that panel that comes
in with no mirrors on it.

And then, when it goes out,
it looks beautiful, all polished up.

And you know it's serving a purpose
up there to protect the spacecraft.

You stand back and look at it
and go, "Wow, we did that."

A thin silver surface of mirrors
will reflect the sun's rays

away from the satellite and is
its last form of heat defence.

These are 100 microns thick.

So they are very thin,
it's about as thick as a human hair.

We have sheets of 198 mirrors
at a time, so they're very fragile.

The glass the mirrors are made of
also helps to emit heat

away from its core.

Just want to feather that in.

Well, we've put the activator in
and we've only got 30 minutes

to apply the adhesive, put the
mirrors on and get it under vacuum,

So, it is a bit of a rush.

It's eight hours of prep
for 30 minutes of organised chaos!

The surface that you can see
is 99% silver,

it's pure silver.

And the back surface, the darker
side, is nickel and chrome,

which is called nichrome

and that is there purely to stop
the silver from oxidising.

I you remember,
if you can think back

to your grandmother's silver
dinner service when it goes black.

These will go black and they then,
they don't become reflective.

That's it. We're done.

In Portsmouth, Ian Kilby is putting
the communications module

through its final checks

in a special room
called an anechoic chamber.

We're firing some microwaves
at the payload

to see if there are any leaks
in any of our co-axial connections.

So, if you imagine the same signal
is inside the payload,

it's leaked around
and it's coming out of a hole,

it could, in turn, effect the input
into the satellite

and the output going out.

So, it could blind itself,
in effect,

with its own loop of RF signal.

It's been quite catastrophic
in the past to have EMC leaks

because it actually interferes
with the transmission

that's coming from
the comms module back to Earth.

The chamber is designed to block out
any radio signals

from getting in or out.

It's almost like taking
a telephone towards a radio

when you're phoning
the radio station.

You get that a big screaming squeal,
in an effect not a screaming squeal,

but obviously it has a similar
effect on a telecoms payload.

With the final testing complete,

it's time to box up
the communications module

ready for shipping.

It's always a nerve-wracking moment
to pick up something of this value.

It's all the fruits of our labours
over the last few months.

Lots of things
potentially could go wrong.

You know, we're picking it up
with a crane.

Failure with the crane or
something catastrophic could happen.

Even when it's turning into the box,
it's quite a nerve wracking moment,

it's quite a large mass.

After over two years of intense
and complicated engineering,

most of the work that takes place
in the UK is done

and the modules are shipped
to Toulouse in the south of France.

It's always quite pleasing
when you see another delivery
going out of the door.

It's in this facility
where the final assembly happens.

It's a complicated
and delicate process.

First, the service module
made in Stevenage

and the communications module from
Portsmouth will be joined together.

Then, the solar arrays are added.

Finally,
the antenna will be attached.

Graham Viney has escorted
the service module to Toulouse

but luckily for him
it's his French colleague,

Pascal Gaudin, who's in charge.

This phase is key for Pascal,

he's responsible
for the integration here.

For me, you can probably tell
I'm a little more relaxed,

but I understand what Pascal
is going through, but it's not me.

Here, at that point,

we have a few millimetres, really,
tolerance, that's all.

We are all feeling
a bit nervous about this

because we have to look
at all the proximities

between the two structures

and spacecraft is never the same,
so each time there are surprises,

so, we have to be very careful
about this operation.

After six hours careful work,
the two British built modules
are successfully coupled

and the main body of the satellite
is complete.

I think more relaxed,

we passed the most critical phase
of this operation.

Now we still have to fit all
together the different interfaces,

which are on different levels

but so far it's a success,

yes, this coupling is a success.

Completing the satellite in Toulouse
will take another seven months

of dedicated work.

Although all satellites
carry fuel for the engines

they are actually solar powered.

My name is Ludwig Grandl,

I am the manager for the Centre Of
Competence of Astrium Solar Arrays,

here in Germany.

For the last 40 years, the main
centre for solar array production

in Europe has been this factory.

The satellite will have over 20,000
individual solar cells,

each helping to generate
the electricity needed

to power the electronic systems.

What you can see here,
that's a typical solar array

for our Euro star programmes.

One wing as we see it here
completed with the mechanism

is around 130kg.

Though, on a satellite
we have two of them.

Each array is 20 metres long
and yet their combined total weight

is the equivalent
of just three average sized men.

The arrays are folded

against the satellite's structure
for the launch,

but once in space,
they gently unfold,

using a system of springs and wires.

Let me say, we are extreme reliable
in this way

and we never lost function
of one of our solar arrays

for whatever reasons.

The solar arrays are dependent
on a drive mechanism.

This allows them to move
and always face the sun

and this machine has been
designed and built back in the UK

by Bob and his team.

This is one of the key critical
elements in the spacecraft,

so it has to operate every day
for 15 years.

If we lose this,
we lose power into the spacecraft,

that causes the mission failure.

This mechanism is one of the most
critical components

of the whole satellite.

It has to move the solar arrays
to face the sun every second

of every day for its entire
15 year lifetime.

Because if it doesn't,
the satellite will loose power.

This provides two functions.

It provides the power transfer
from the arrays

and then it also enables the arrays
to track the sun

by rotating at one cycle per day.

This is the spacecraft.
These are the arrays.

So, they sit in here holding
the arrays

and if you imagine my fist
as the Earth

and the camera perhaps as the sun,

then as the Earth rotates
and the spacecraft rotates,

you'll see that if you don't rotate
the array to track the sun,

then you don't get the power.

So we have to rotate,
as this space craft sits

in geostationary orbit above the
equator, moving round the Earth,

we have to rotate these
so they are always facing the sun.

There is a very,
very high pleasure in engineering

in getting something right.

The fact that you can see
something which was,

in effect, something in somebody's
imagination turn into reality

and for it then to be successful,
is a tremendous kick, it really is.

With everything fitted and tested
the satellite is carefully packed

into a hi-tech crate and sent
by plane to the launch site...

..Where it's prepared
for its final journey.

It's a tense time
for the whole team.

We're in the satellite control
centre and this control centre

takes over control of the satellite

after it's separated
from the launcher.

It is critical,
it is a crucial phase.

Good line pressure to fire
the thrusters.

At the moment, this team here
is running through a rehearsal.

There is a computer simulating
everything the satellite does,

we can send commands as we would
and it responds like a satellite,

and it's really testing,
testing the team.

As the satellite is being prepared
for launch

on the other side of the world,
these rehearsals are critical

because when it leaves the rocket
that gets it into space

its orbit will be elliptical.

The moments leading up to the firing
of that main engine is very tense,

a lot of pressure,

and if it doesn't happen we have
a lot of people looking at us.

Graham and his team will then have
to fly it into the correct
geostationary orbit

by remotely operating
its main engine and thrusters.

Each burn will take
up to 90 minutes, but overall

the procedure will take two weeks
and use half of the available fuel.

Every time we circularise the orbit
of a satellite, there's something

about those two weeks where
something will challenge us.

The launch day is fast approaching.

And over 4,000 miles from Stevenage,

Bob Graham is following
the satellite's journey.

We're in French Guiana,
which is in South America

and very close to the equator.

Green, lots of green trees.

Very, very hot, about 37 degrees
today.

One of the reasons we launch
from the equator,
or very close to the equator,

is because the earth spins

and there's a faster rotational
speed actually on the equator.

It makes business sense to fire
a rocket into space from the equator

as it's cheaper to launch.

Which means less fuel,
means a lower cost launch

and from
the spacecraft's perspective

it's actually being placed closer
to its end orbital position

so, again, it uses less fuel
on the spacecraft.

The satellite will be lifted
into orbit by an Ariane 5 rocket.

At over 50 metres
and almost 800 tonnes fully fuelled,

this is the workhorse of European
space exploration.

Our satellite is right at the top
of the launch vehicle

you can see the fairing at the top
the curved part

is literally sitting
right inside there.

Watching the launch has
a special resonance for Bob.

I've worked in the space
industry for nearly 30 years,

never seen a launch
in my whole career, never.

To be so close is a really
incredible and moving moment

because a lot of people do not
actually get to witness this.

I feel terribly privileged
that I'm here

and I would see myself
as a representative of the people

who've actually contributed
to the delivery and the success
of this spacecraft.

You're talking about 30 million
horsepower at launch.

So, the thrust when this vehicle
takes off

is about the equivalent
of 12 A380 airbuses taking off.

This is a pretty rough
ride for the satellite

and that's what all the design
and everything is about.

We have to make sure
it survives this phase

and then it can go into operation.

So, it's, er, yes,

this is the bit where we all get
that...little bit of butterflies
in the stomach,

which is saying,
"I hope this goes all right."

Maybe even some sweaty palms,
let's wait and see.

Later that day,

the rocket is carefully rolled out
to the launch pad.

It's taken over two years,
in excess of £100 million

and some exceptional engineering
to get this far.

And now, there's nothing Bob can do.

Except wait.

Launch day.

And on schedule,
the automatic countdown commences.

At first,
everything goes smoothly.

But at just 1 minute and 47 seconds
before ignition,

the countdown stops.

The window has opened
and there's a hold.

There's some problem somewhere
which they're checking.

They'll restart
the seven-minute countdown.

So we will see how it goes from here.

Little butterflies.
Is it going to go? Is it going to go?

And is it going to be...

..as they say it is
in terms of the light, the noise

and, er...yeah.

So let's see.

As night falls, it's apparent
that the technical issues

are more serious
than first thought.

And after an hour of waiting,
the launch is cancelled.

The next morning,
an initial investigation suggests

a faulty fuel valve in the rocket
caused the postponement.

Here we are in Mission Control
Jupiter, the morning after.

This is the place where that final
decision was made last night

to postpone it.

As an engineer,
I know this is the right decision.

The decision made last night
was the right one. But...

..as a man, as a person,
as a representative of a team,

yes, there's an element of
disappointment that it didn't happen.

Space is difficult. It is about risk.

It is about showing
that our products are good,

but we can't afford to take
the risks. But it will happen again.

Maybe I won't see it, but others will
and I guess that's life.

And finally, the satellite
was successfully launched.

Today, 35,786 kilometres above us,

the brand-new
communications satellite

is now being prepared to broadcast
pictures directly into your home.

So keep watching the skies.

From sketch to structure, see how
designs come to life by visiting:

And follow the links
to the Open University.

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