Hundreds years ago people thought that the earth is the center of the universe. Later Copernicus found that the sun was the center but not the earth. Now we know that earth is just the center of solar system which is an extreme small part of the whole universe. Suppose that you have the power to change the orbit of all the planets in the solar system, can you imagine what will happen? Orbitrunner is an arcade game on www.flash-game.net in which your mission is to control the sun with your mouse and manipulate the planets’ paths. The sun’s pull gets stronger as planets get closer. If the gravity is at a right angle to the direction of travel, an orbit can form. Make sure the planets will not leave the screen or collide. Have fun!