Astronomy Java Applets

These applets were written when I was working for the Physics and Astronomy Department at the University of British Columbia.

Some of these applets contain deprecated features (the Black Body applet, in particular). I'm slowly working to update these applets, but they may cause some browsers to crash. New versions will appear at my CECM applet page first, and then moved here.

I strongly advise people to use the latest Java plugin from Sun (JRE version 1.4 at least). On some platforms, this greatly increases the performace, sometimes by as much as a factor of 10.

If you have any questions, feel free to contact me.

Rob Scharein (
Centre for Experimental and Constructive Mathematics
Simon Fraser University
7 October 2004

Solar system explorer

Click on Saturn to follow a link.
Phases of the inner planets (interactive Java animation)
Retrograde motion (interactive Java animation)
Kepler's Laws (interactive Java animation)
Cratering (Java applet)
Solar Eclipses (interactive Java animation)

Simulations and Animations

Click on the image to run the applet of your choice.

Fusion in the Sun!
Big Bang!
1 over R squared
Extrasolar planets
Search for Black Holes!
HR diagram simulator
Eclipsing binary stars
Proper Motion
Doppler effect
Blackbody radiation

Telescopes and Observatories

Click on the image to run the applet of your choice.

Snell's Law
Simple Lenses and Mirrors