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STEM Software
Before using the applets below, you will need the latest Java Plugin... You can find the appropriate plugin at the sites listed below:
For PC Users: You need the J2SE 1.4.2_06 JRE includes the JVM technology. Click "Download Now" and pick your operating system For Mac Users: You should have plugin already on your computer (It comes standard with OSX). To run an applet, you must first download the .jar file. Then click on the coffee cup below for instructions to run the .jar file.
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PlanetFinder is an on-line learning module. It instructs students how astronomers fit model Doppler velocity curves to data representing extra-solar planetary systems. This module can be run from the University of Colorado servers, or downloaded, installed, and hosted on your local servers.

Read about Planetfinder here.

Run PlanetFinder now on our server

PlanetFinder - Instructor Access: Setup an account and prepare a session for students.

PlanetFinder - Student Access: Try the module right now. Use sample for the session name and group password.

Download and run on your server
  • PHP 5.2 or greater
  • MySQL
  • A web server (such as Apache)
  • A little know-how to set up a website (such as your system admin)

Download basic PlanetFinder (.tar.bz2 format, 1.18 MB): Contains website and applet.

Download PlanetFinder including the exoplanet mirror (.tar.bz2 format, 16.65 MB): Contains website, applet, and a mirror of the The Extrasolar Planets Encyclopaedia in case it cannot be accessed.

Download just the Extrasolar Planets Encyclopaedia: Download .tar.bz2 (15.47 MB) Download .zip (52.84 MB)

Source Code
Download the Java source code to Planet Finder applet
Just the extra-solar Planet Data
Standalone extra-solar Planet Data

Planetary Transits

Planetary Transits: A visualization/simulation of the extrasolar planet searching technique. The user can control planet size, orbital radius, and randomized error. (ctrl-click here to download .jar file)(click here for Java source code) Click here for a descripton and lesson plan.

Simplified Planetary Transits: A simplified, more focused version of Planetary Transits(ctrl-click here to download .jar file) Click here for a lesson plan.


Galactic Communication: A visualization of the "Drake equation" and more. Demonstrates how the probabilities of contacting and communicating with extraterrestrial civilizations depend on the birth rate of civilizations and their mean lifetimes. (ctrl-click here to download .jar file)(click here for Java source code) Click here for a lesson plan.

Binary Star Orbits: A simulation/visualization of orbits of binary stars. User can control all orbital parameters. Applet displays views of orbits and a dynamical graph of the Doppler shifts of each star.(ctrl-click here to download .jar file)

Radiative Transfer: Simulates the propagation of photons through a slab of atoms. User can control the number of atoms and the absorption and scattering cross-sections as functions of color. (ctrl-click here to download .jar file)(click here for Java source code) Click here for a lesson plan.

Random Walk: A simulation of random walk in 2 dimensions. (click here for Java source code) Click here for a brief description of the theory of random walk.

Doppler Shift: A visualization/simulation of Doppler shifts of sound waves. The user can control the sound speed, frequency, velocity of source or receiver. (click here for Java source code)

Eclipsing Binaries: A visualization/simulation of the phenomena of eclipsing binaries measuring total system brightness. The user can control star radius, temp, orbital radius, inclination , and randomized error. (ctrl-click here to download .jar file)(click here for Java source code)