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What is electric propulsion or ion propulsion?
Electric propulsion is the use of electrical energy off a satellite to accelerate a gas
and then create thrust.
Our nation has gone to a global, space-based infrastructure.
If you receive Sirius XM Radio or Direct TV, it's provided by a satellite 20,000 miles
above you.
And that satellite has to be positioned directly above you at all times.
However, we can't hold a satellite perfectly still and the earth is not perfectly round,
so it tends to drift over time and we need a propulsion system to hold that satellite
in position above you at all times.
Traditionally, we provide the propulsion with chemicals.
That is, we mix a fuel and oxidize it together.
We get a high pressure, high temperature fire, just like you see on the Space Shuttle, and
that's how we hold the satellite in position.
The problem is that eventually, that satellite runs out of fuel, and when it's out of fuel,
the satellite is effectively dead.
We've overcome that limitation with electric propulsion.
By using electricity off the satellite, we can simply turn up the voltage on the engine,
increase the efficiency, and now we get more miles per gallon for the fuel on that satellite.
We use that capability to make the same satellite with the same performance, but with less propellant,
which means a smaller satellite.
We can now launch several small satellites off of a single launch vehicle.
This reduces the cost of putting that satellite on orbit and eventually reduces the cost of
beaming the information to you.
So, what is the impact of electric propulsion on your life?
It actually reduces the cost of getting information beamed to you from space.
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