Gravity is a program to simulate the path of move for bodies (altered by the gravity drive between each other, i.e. a gravity simulator.

By using this program, gravitational attraction may be better learned. From the simplest orbit to complicated galaxy crashes, there is a wide variety of motions by gravity.

On simulating the motion of two bodies, it is conspicuous to model the elliptic orbit around each other's mass center of the Sun and the Earth or the path of a rocket as leaving the Earth with the speed of escape or the see-saw maneuver of a space probe, when gaining speed (kinetic energy) from a planet.

By modeling multiple bodies, you may observe the perturbance of planets interfering with each other, ejecting a body from the system or when a planet capturing a body that arrives from the outside and making it a satellite of its own.

Here are some key features of "Gravity":

· The number of bodies that can be simulated at the same time is (theoretically) not limited. (practically it can be maximum a few thousand, the movement of a few hundred can be seen as continuous on the screen)
· The bodies can fall under 16 different groups that have a common center of mass
· Extreme events of the bodies (collision, to close proximity to each other, exceeding velocity) can be screened out
· Trail (with the size of the body or a pixel, even the same color)
· Velocity and force vectors (with trail or not, even the same color)
· Modification of the virtual size of the vectors
· Modification of view and zoom by the mouse, even under simulation
· Modification all system parameters under simulation
· Automating restarting of the simulation
· Creation of the bodies by the mouse
· Creation of several bodies at the same time (in the form of ellipsoid or text)
· Search of bodies and their center of mass
· Saving the data of the simulation into a file
· Export and import of the system data