The Earth never stays in the same place in space. It's always moving--and really fast, 107,218 km/h. It orbits the sun for one thing. It moves in a huge circle (really an ellipse) around the sun, once a year. This happens because of gravity. The mass of the sun keeps the mass of the Earth rotating around it due to the gravitational forces between the two. But the sun is also moving really fast, so we are moving with it, too, at about 781,000 Km/h. The earth also rotates, so if you are on the equator, you are zooming at about 1,674 Km/hr just because the planet is twirling around. Point is: nothing stays in the same place in space. Everything is always moving.