gravity_alpha

In order to predict/calculate object properties in future time one need initial position and speed at some initial moment of time (of course, within limits of calculation).

For calculating positions and velocities, numerical method for solving differential equations is used.

There is no limitation in parameters - object will behave just like they behave in the real world. The only thing which is not ‘real’ is an option to increase the object sphere beyond physical meaning (unrealistic small density). So, be careful with initial data - you will see same behavior as in real world with real objects - of course, within variables, calculation and display limitations.

Data is calculated and displayed in SI units (second, meter, kg, meter/second etc.). For an example, you can check if your data for sun and earth are correct by watching amount of time elapsed for one earth revolution around sun.

You can download and run the install package but beside that, this application is portable, it does not write anything to registry (or anywhere else). This application does not 'phone home' or collect any user information in any way.

* an option to add image to object is just for fun - it has no real purpose in this software

** objects (like earth) will NOT rotate (spin) around itself because the gravity force (alone) do not make them change rotational state