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If you look up, there are 4,708 satellites that came from earth currently orbiting our
planet. Just in the portion of the sky you can see, hundreds of satellites are passing
overhead at any given time. You often can't see them, but they're there making GPS work,
taking images of earth, providing communications, even spying for governments. These satellites
are some of the most expensive single objects that can be made. If you took at tennis ball
sized chunk of the Hubble Space Telescope, it would be worth over $1,500. Modern full-scale,
commercial grade satellites cost in the hundreds of millions of dollars. They're just incredibly
complex objects that require years to construct. Many of the satellites flying over you right
now, though, started their life here at SSL in Palo Alto, California.
SSL is a commercial company owned by Maxar Technologies specializing in satellite and
spacecraft construction. They've built spacecraft that are current in orbit for everyone from
DirecTV to national governments. If you've ever watched satellite TV, listened to satellite
radio, or used satellite internet on a plane, there's a decent chance you've directly
used one of the satellites they built here in their factory. But let's say you want
to buy a satellite from SSL, what do you do? "Well the first thing you do is you pick
up the phone and call us but the next thing you should do is check your bank account to
make sure you have enough money to buy a satellite. Satellites, depending on what kind it is and
where it's going can cost tens of millions of dollars up to several hundred million dollars."
Once a customer makes that first phone call to SSL, there will then be an ongoing back
and forth between them and the customer. Essentially, the customer will tell SSL what they want
their satellite to do and SSL will come back to them with a price. Eventually, if all goes
well, they'll sign a contract. That's exactly what happened a few years
ago between SSL and Telesat—a global satellite company headquartered in Canada that owns
and operates a fleet of satellites. Their satellites are used to broadcast signals,
whether it be TV, Radio, or Internet, for their customers—satellite TV, radio, and
internet providers. In this case, Telesat needed a satellite to provide additional capacity
over the busy North Atlantic region and so they came and signed a contract with SSL to
build their new satellite—Telstar 19 VANTAGE. Soon after contracts were signed, work began
on designing the satellite. In that process the designers usually pull designs for some
more generic aspects from previous projects and then modify them to suit the particular
job. The length of that process can vary widely based off how complex the satellite is but
throughout the process, as soon as they've locked a design in, they'll begin ordering
parts. SSL builds about half their components themselves and orders the other half from
other companies. The decision on whether to order or build in-house usually comes down
to performance. "There are certain components where, depending on what the requirements
are we build higher performance components than suppliers, some of them our suppliers
build better components than we do." Over the years SSL has looked at what it's good
at and what other suppliers are good at and made the decision on what to order based off
that. For example, one of the components that SSL builds are the antenna reflectors. These
are what actually direct signals down to earth and each of them is custom designed for the
region that the satellite will cover. "So this is, for example, for Telstar 18 Vantage,
you can see here that these are these reflectors that would be sticking out on the side and
it's used for sending signals back to earth and all those little dots you see on there
are for photogrammetry so they're used to make sure that the surface is actually exactly
as designed so we have these cameras that take pictures of these and all the dots to
make sure that it was build according to the design." The satellite these antenna reflectors
eventually went on, Telstar 18 Vantage, the sister satellite of Telstar 19 Vantage, will
launch in late August 2018 and soon after will go into service providing data services
over Asia and Oceania so the antenna reflector was carefully crafted to provide signal over
populated areas and busy flight and maritime corridors while not wasting resources on providing
service to areas the company already has coverage for or that would have little demand such
as to the south of Australia. About 9 to 15 months after ordering, the majority
of the ordered components will start rolling through the door and then the bulk of the
assembly process begins. This process is too complex to go into detail on, but essentially
they'll first build the major elements separately. One group will assemble the propulsion system
and framework of the satellite while another will assemble the payload, what the satellite
is actually built to carry whether that be an advanced camera or a communications system,
while yet another group will assemble the super-light and efficient solar panels that
will power the satellite when in orbit. The assembly of the different major components
will take a few more months and then they'll start to compile those different major components
together over a period of a few more months. Each component is tested independently before
and while being installed on the satellite, but once they're all pieced together there
begins an incredibly rigorous phase of testing the satellite as a whole. When buying a satellite
from a trusted manufacturer like SSL, the customer is buying reliability so there can
be no compromise on testing. They need to be sure that the satellite will actually survive
launch and work in space and the best way to do that is to just simulate launch and
space. There are three major factors that could harm a satellite—vibration, temperature,
and sound. The vibration comes as a satellite launches
in a rocket so they test that their satellites can survive launch. "When you put these
satellites on top of a rocket in the payload faring they experience a lot of vibration
loads in the x, y, and z so we're able to simulate those with this vibration table.
It has a baseplate there and you can shake it in this direction, in this direction, or
in this direction so it does in all different directions to simulate the environment and
make sure that it's all operating." The satellite on the table in testing here is
Telstar 19 Vantage itself. This here is just one of many tests where they literally just
shake the satellite and see how it responds. They only last about 60-90 seconds each because
that's how long the satellite will experience vibration during launch until the rocket reaches
the upper atmosphere. They'll also test to be sure that their
satellites can survive the vacuum and temperatures of space. "So, what you see up there, this
big blue pumpkin looking thing like Cinderella's carriage, that one is called our thermal vacuum
chamber, we like to call it the blue pumpkin, and what we use it for is to simulate the
thermal vacuum of space so we'll go down to the vacuum levels of space, you know 10-10
TOR, and we will turn on the payload on different parts of the satellite to make sure that everything's
functioning properly when you put it in space and in addition to that, once it's under
vacuum, we have these thermal panels in there to simulate the hot and cold environment.
So like, when you're facing the sun and the satellite gets really hot, we bring those
temperature to bear and then we make it really cold when it's facing away from earth in
an eclipse type situation and make sure everything's functioning properly."
Lastly, launch is very loud to the point that the acoustic energy could actually damage
a satellite so they make sure it doesn't by simulating the launch environment through
bombarding the satellite with acoustic energy with speakers. There are a myriad of other
tests performed before the satellite is given SSL's stamp of approval, but once it's
ready, the satellite does, of course, need to get to the launch site. The customer decides
which launch provider to use whether it be SpaceX, United Launch Alliance, Arianespace,
or another so the satellite might only need to go as far as Vandenberg Air Force base
a four hour drive away or as far as Baikonur Cosmodrome in Kazakstan.
The launch site is also partially decided based off what sort of orbit the satellite
is going into. If a satellite is going to orbit in a north-south direction over the
poles they want to launch in that direction so they want to launch from a site with open
water to the north or south both for safety and, for some rocket designs, so stages of
rockets can fall into the ocean throughout the launch process. SpaceX, for example, therefore
uses Vandenberg Air Force Base in California for their polar orbit launches as it has the
Pacific Ocean directly south. For geosynchronous orbits where satellites travel from west to
east at the same rate as earth rotates they want to launch in the same direction as the
satellite will orbit. For that reason they can't launch from Vandenberg as it has land
to the east so SpaceX uses the launch pads on Cape Canaveral, Florida as they have the
Atlantic Ocean to the east. In the the case of Telstar 19 Vantage, it was going in geosynchronous
orbit in order to stay consistently over it's service area so SSL needed to get the satellite
all the way across the country to Florida. No matter where a satellite is going, it gets
packed up into one of these specialized shipping containers. For travel to closer launch sites
within the US they'll often drive. They'll put the container on a truck driven by trusted
oversize vehicle drivers, have a lead vehicle checking for obstructions, a trailing vehicle
watching to make sure nothing goes wrong, and for longer drives a motorhome so drivers
can swap out and rest while still moving. If the launch site is far, such as the ones
overseas in French Guyana, in Kazakstan, or even the further ones in the US such as Cape
Canaveral they'll fly the satellite over in an Antonov cargo plane. Satellites arrive
to their launch sites at least a month before their launch as there's plenty of last minute
preparation to do. They have to perform additional testing to make sure nothing was damaged in
transport, fuel it up, and mount it in the rocket.
Once that happens, though, there's a period where there's really nothing for SSL to
do. "As they go through the process of the countdown there are a number of places where
we're asked to confirm that we're ready for launch, then they launch us and at that
point we can no longer monitor our satellite until we're off the launch vehicle so for
about a half hour we're hoping that the launch vehicle guys are doing everything ok
and they usually are." In the case of Telstar 19 Vantage, the customer entrusted SpaceX
with the responsibility of getting their satellite to orbit so on July 22nd, 2018 at 1:50 AM
a Falcon 9 rocket lifted off from Cape Canaveral carrying SSL's latest creation to space.
The launch of this satellite actually made the record books as it is the heaviest commercial
communications satellite to ever be entered into service at 15,600 pounds. On that early
morning in July, the Falcon 9 gained altitude as it flew south-east over Africa, then 32
minutes and 40 seconds after launching, 358 miles above Mozambique, Telstar 19 Vantage
was released from the rocket and gently pushed forward in the first moments of it's 15
year long orbit of earth. At that point, the work's not done for SSL,
though. Their job is not just to build the satellite but also to enter it into service
in space. Once the satellite is deployed, SSL will look for its signal and establish
communications. "We start commanding the satellite, we tell the satellite what we want
it to do, we start to get the satellite into a safe position after launch, we'll deploy
solar arrays so we can start generating power, we'll start to activate everything on the
satellite and we'll put the satellite in the safe condition so that the crew can start
to get some rest." Over the next ten days there's a process of firing the satellite's
engines to raise it from the altitude of 350 miles where it was deployed to 22,000 miles
where it will stay for its service life. There's then another two to four weeks of testing
to make sure everything survived launch and then, finally, after years or work, it's
time to hand over the satellite to Telesat, the customer, so they can put it online and
start operating it commercially. At that point, after years of work the satellite can finally
itself be put to work. One of the aspects of how satellites work
that I found most interesting to learn about when I filmed this video was on how orbits
work. The science of how you can make an object orbit at such a consistent speed that it will
stay still over one particular area of earth is fascinating and if you want to learn all
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