Why is it important for satellites to be outside the earths atmosphere?

Answer 1

Satellites need to be out of the earth's atmosphere or the gravity would make them fall to the ground. In space, the satellites are also able to orbit the earth effortlessly because they have less weight.

Answer 2

Anything that moves through the Earth's atmosphere with substantial speed experiences friction that acts against its motion. In the case of a satellite, this will cause the orbit of the satellite to decay and the satellite will eventually burn up as it falls back to earth.

Some satellites in low orbit are not entirely outside the atmosphere. They experience atmospheric friction and decay from orbit in weeks or months.

Satellites further away from the earth experience less friction, sometimes effectively none, and are said to be outside the atmosphere. They can stay in orbit for a very long time. This can be important for some functions, like communications satellites, where the less often they must be replaced, the less costly the project is.

Within the Earth's atmosphere, the atmosphere will brake them, they will quickly lose all their energy, and fall to Earth.

Answer 3

If a satellite is inside the earth's atmosphere, then aerodynamic drag would cause it to slow down. This would result in its losing altitude. It would then be in denser atmosphere and so slow down even more. It would end up crashing into the earth or burning up in the process.