Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
A satellite is in a circular orbit up. How much energy would take it from there to very far away? Compare with the energy to send it far away from rest on the ground. (, .)
In a circular orbit of radius : , , independent of the satellite's mass. Its energies: , , .
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. From orbit. .
Step 2. From the ground. .
Answer: from orbit, against from the ground.
Watch out. In orbit, the satellite already has kinetic energy; it needs only more.
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