Well, this animation is 1024x768 pixels. I made it to be a stand-alone,
and in all probability you won't be able to see all the controls if you
view it in a browser window. My suggestion (unless you want to buy the
stand-alone), is to get Shockmachine^TM   (FREE!) from Macromedia,
and make sure you have the latest Director plug-in with the
Shockwave Remote player. This player has a button on the upper left
that allows you to save an animation to the ShockMachine (not all
Shockwave animations can be saved like this - the author has to code
things to allow it; I have done so with this animation; this is
indicated by the save button having a red triangle in it). You can
then play the animation using Shockmachine, which means if you set
Shockmachine for full-screen it will play the animation to almost
100% scale, and it will show all the controls.

As to that, at the start there are 3 planets (in the shape of regular
rhombic dodecahedra) on the screen. Two are light, the one in the
middle is heavy. You can't change the heavy one at all, but you can
drag the light ones to new positions, and set their initial 3D velocity
vectors using the associated fields (use numbers! I don't recall if I
put in a check for nonnumeric data). This is REAL 3D. The arrow in the
upper right starts the thing.

Once going (neat orbits, 1/r² interaction - if they get too close
they may go wild and leave the screen) there are three controls.

• lower left: zoom in; zoom out.
• lower right; rotate.
• Upper right; reset.