Why don't satellites in orbit fly off in to space

The satellites we launch are launched with a precise speed (~28'000km/h) and at a precise altitude (~36'000 km) so that in the influence of the Earth's gravitational field just balance their speed. That way, they stay at the same altitude.

From the degree of the air/atmosphere around a planet they create a source of gravity which is also called the ozone layer of a planet which could launch different degrees between each planet. Ever since Earth's magnetic pole was weak it caused the ozone layer to launch anything from it was not possible.