What holds the earth in space?
It was proved long ago that :tit’s orbit of the earth is safer than the sturdiest of railroad tracks. The same holds true for the orbits of our sister planets. In fact, our Solar System is a secure and stable unit. Its members are held in their places by two great laws which govern the universe. The orbiting earth is engaged in a mighty tug of war. The two opposing teams are invisible forces which govern all of the heavenly bodies and keep them in their places. The force of the suns gravity pulls our world towards the sun, just as the earth’s gravity pulls a falling stone to the ground. Centrifugal force pulls the earth in the opposite direction and keeps it from falling into the sun. You can see the force of gravity at work when you drop a stone and watch it fall. You can see centrifugal force at work when you tie a string on a ball and whirl it around and around your head. If you let go or if the string breaks, the ball will fly farther away from you. This is because a whirling body
