What is the primary force causing most near-Earth satellites to require propulsion systems?

Answer

Atmospheric drag acting as a continuous brake

The tenuous remnants of the atmosphere in Low Earth Orbit (LEO) cause atmospheric drag when the satellite moves at high speeds, continuously bleeding off orbital energy and causing altitude decay.

What is the primary force causing most near-Earth satellites to require propulsion systems?

#Videos

Satellites That Scoop Air And Use It As Propellant - YouTube

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