Up arrows = Power Engines Left and right arrows = Turn Spacebar = clear pen Greenflag = reset defaults 1 and 2 number buttons = change number of planets Credit to Isaac Newton for gravity equation: Force = (MassA * MassB) / Distance You can see gravity's force on you in the upper right corner of the game
All objects attract to each other. Your hand attracts a tennis ball, and the tennis ball attracts to your hand. However since your hand and the ball, both have such little masses, the gravitational force is too small to notice. Earth is like a big tennis ball. It has so much mass that it can attract your hand. If you let your hand be loose, it will fall to the ground. Try spinning a string with a rock on it. In this analogy, the rock is your space ship, your hand is a planet, and the string is gravity. If the string rips, the rock will keep going in the direction it was going. The only thing keeping the rock from flinging out is the string/gravity. This force that makes the rock want to fling outwards is called centrifugal force. So what keeps the space stations in orbit around Earth from falling? The answer is the same thing that pulls the rock spinning on a string outwards. Centrifugal force. The faster you spin the rock, the stronger centrifugal force will be. To get a space station into orbit, huge engines need to push its speed so high, that the centrifugal force will balance with gravity. A good way to think of an orbit: If you throw a rock, it will fly in an arc shape and hit the ground. What if you threw a ball so far it went over the horizon? It would keep falling but never touch the ground! If a rocket wants to make its orbit bigger, all it has to do is increase its centrifugal force by increasing its speed with engines. If the orbit needs to be smaller, the rocket turns backwards and slows the speed down. If the pilot wants to land, he lowers his speed so much that the rocket will touch the ground. Notice that making adjustments on one side of the orbit, will only affect the other side of the orbit. This can be useful if the pilot wants to make an oval orbit. To get to the moon, astronauts made their orbit around Earth a big egg shaped oval. When the rocket was on the far side of the orbit, they maneuvered to orbit the moon. Then they decreased their moon orbit size so that they would touch the moon. The rocket's powerful engine slowed it down so it wouldn't crash. Touchdown! Small Planet mass = not as much centrifugal force needed to counter gravity = not as much speed needed Huge planet mass= a lot of centrifugal force needed to counter gravity = a lot of speed needed Big orbit = long distance to planet = not as strong gravity = less centrifugal force needed = less speed needed Small orbit = short distance to planet = strong gravity = high centrifugal force needed = high speed needed A black hole is a planet that has attracted so many other planets and gained so much mass, that it even sucks in light! And yes, you can orbit a black hole. In fact the entire galaxy orbits around a black hole in the center. Setting the planetMass to 5000 kinda simulates a black hole.
