Far out in space, a satellite circles the earth. What keeps it from crashing into the earth? And what keeps it from sailing away into space?
Two kinds of forces work to make the satellite circle the earth. One is the tremendous push of the satellite’s speed – thousands of kilometres per hour. Without this push, gravity would pull the satellite back to the earth.
The other force is the pull of the earth’s gravity, which reaches far out into space. Without this pull, a satellite would travel in a straight line, away from the earth.
Gravity pulls the satellite towards the earth. But the speed of the satellite pushes it outwards. When the push and the pull are even, the satellite can’t sail away from the earth – or fall back to the earth, either. Instead, it speeds around the earth, making a circle in space.
Picture Credit : Google
