SOLAR SYSTEM

Detailed explanation-1: -A satellite must remain above the atmosphere because air resistance would not only slow it down, but incinerate it at its high speed.

Detailed explanation-2: -why are satellites and other objects launched to altitudes above 150 kilometers? The force of gravity on satellite above 150 kilometers is almost as strong as it is at the surface and this high altitude puts the satellite beyond the reach of Earth’s atmosphere, Air resistance almost totally absent but not gravity.

Detailed explanation-3: -g is equal to 9.5 m/s2 at 100 km altitude, which is 9% larger than 8.7 m/s2. However, at 500 km altitude, g is close to 8.45 m/s2, which is close to 3% smaller than 8.7 m/s2.