Answer: Gravity.
Step-by-step explanation:
Earth and other objects would have fly off into space in a straight line if there would have been no gravity in between objects.
The gravity can be defined as the force between two objects in space which keeps two objects together in the space.
It is also responsible for holding the objects in space, making them move on their orbits, not allowing the heavenly bodies to crash.
So, there would be no gravity the objects will fall off in a straight line and none of the objects would be at its specified position.