Launch small satellite?

Question

I want to build a small satilite and launch it into low space orbit. Nothing 'too fancy' a Raspberry Pi to power the systems, camera which'all transmit video and also a radio reviver and transmitter, maybe a small power bank to power the Pi and solar panels to charge that and gyro for stability in space instead of multiple thrusters. Hopefully it should last a few weeks before it burns up. The weight of the satilite would be under 5Kg. Also would radiation cause any short term harm to the electronics?

I was also thinking if I could first launch it with a weather balloon, have a small chemical rocket fire just before the weather balloon pops and then once it's reached micro gravity the rocket falls away and a canister of compressed air can accelerate it from there to a distance where should last a couple weeks.

I was also thinking about ion thrusters but they use a lot of electricity

Would this be possible at all?

Answer 1

@antlersoft is right. You'd still need a powerful rocket to get moving fast enough to enter into orbit around the Earth, so probably not, unless it's a really really big balloon holding a really big rocket!

The term "microgravity" might be a bit misleading. The gravity up there is almost as strong as it is on the surface. The key is to go fast enough so that your "fall" towards earth actually ends up being an orbit. That's about 7.7 kilometers per second!!

If you are inside a spacecraft, in an orbit, moving at such an orbital velocity, you would also be in orbit around the earth. If you just look at how your body moves with respect to the spacecraft, you could call it "microgravity" (lots of people do, even astronauts) but maybe it should be called micro-acceleration with respect to the spacecraft.

Without the buoyancy that the balloon provides only while it's within the atmosphere, your rocket would accelerate towards earth. At only say 30km above the surface, you're only 0.5% farther from the center of the earth. Since the force behaves like $1/r^2$ that means gravity is only about 1% lower, so you'd accelerate towards Earth at roughly 8.8 $m/s^2$ instead of 9.8 at the surface, until you got low enough where the air is dense enough to start slowing you down.

So the hard part about getting to - and staying in space is not just the altitude, it's speeding up to that 7.7 kilometers per second that's the hard part.