As I type, there is presently an interesting little web application running through the world of twitter. This is My Solar System 2.0. It is a simulation of orbital mechanics for 2-4 bodies, allowing users to place these bodies in such a way as to create solar systems. One of the bodies could be a moon, another a star, perhaps the last two ordinary planets. You can define the initial positions, velocities and masses of the objects involved and if you want hints on where to get started – there’s a few situations (including gravitational slingshot, four star ballet and binary system with planet) already preset in the drop down menu to the right.
I got a link to this from @SheldonCooper, a twitter account associated with the Big Bang Theory character whose granny calls him Moon-pie. I retweeted this in the hope of providing @David_Kipping a game he can play whilst allegedly doing something tangentially related to his own work (using photometric and spectral data to determine the orbits of exoplanets). But it was picked up by @astroengine (Dr Ian O’Neil of Discovery News) and from him @plutokiller (Mike Brown of Caltech, whose discovery of large Kuiper belt objects gave impetus to the reclassification of Pluto). So now half the world’s scientific twitterati is presently playing with what is actually quite a standard teaching aid.
The simulation is from the stable of the University of Colorado at Boulder. I’m pretty sure if you look through all their various interactive simulations, you’ll find one or two from your childhood if you’re of a certain age. One in particular caught my eye, that old familiar natural selection one that involves setting an initial number of rabbits and introducing wolves and disease in order to set a stable and hopefully healthy population that doesn’t overeat. I remember using telnet to get that from the university severs in the earliest part of the nineties, just before the new thing of web browsers made it a bit easier.