Question: What do you need to make a satalliete ?

Camilla Weiss answered on 15 Jun 2015:

Hi 401spcc35 (can I call you ‘4’ for short?),

That’s a really good question, thanks. Aside from a bunch of people crazy enough to try to send something into space you will need the following:

– Power – there isn’t a cable long enough to charge your satellite battery in space so you need to be able to generate power. On a satellite we do this using solar arrays which soak up the sun during daylight and charge the battery for when the satellite passes out of the sunlight.

– Attitude Control – basically where am I, where do I need to be and how do I stop spinning?! The satellite needs to be able to know where it is in space and which direction it’s pointing. It uses magntometers to measure its orientation against the Eart’s magnetic field and star camera’s to measure the stars to determine where it is in space. To stop spinning and make sure it’s pointing the right way we use reaction wheels and magnetorquers.

– Avionics – The brains of the satellite. This basically includes the main on board computer which controls the satellite as well as things like data storage for storing any payload data and a communication structure to connect all the modules to each other so that they can talk to each other.

– Communications – we need to be able to talk to the satellite and tell it what to do (telecommands) and also get data back down about how the satellite is (telemetry), as well as sending payload data which might in the form of images or pure science data readings. The satellite has to have several different antennas and transmitters to do this. They look less like satellite dishes and more like little helices pointing towards the Earth.

– Propulsion – Once you’re in space you need to stay there. When a satellite is in orbit what it means is that it is travelling just fast enough to escape the pull of Earth’s gravity. Over time the satellite might slow down and start to fall back to Earth so you need some propulsion to keep it where it is. You may also need propulsion to get to the right orbit or move out of the way of bits of debris. Most satellites use gas as propulsions but some use more exotic methods like ion thrusters or even nuclear energy!

– Strucure – I’s a bumpy ride to get to space and we need to make sure our satellite gets there in one piece. Once in space the structure is less important but to protect it we need something strong and very light – the heavier something is the harder and more expensive it is to get into space.

– Ground Station – You’ve got a satellite in space, great! Now you need somewhere to control it and receive and send telemetry and telecommands. So some kind of operations centre with a big satellite dish.

I hope that answers your question – if you want any more details just give me a shout.