HORSE is an interactive exhibit that teaches about radio SETI (Search for Extra-Terrestrial Intelligence). It is targeted at an age range of 12 to adult.

HORSE consists of four "pages":

Listen to Space

This page shows a signal from the Arecibo radio telescope, recorded by the U.C. Berkeley SERENDIP project. Noise has been removed from the signal; it consists mostly of RFI. The signal is rendered graphically, as both spectrum and waveform, and as sound. A separate panel shows how the telescope's "beam" (shown as a purple disk) drifts across stars. The user can click to see how an alien signal (emanating from a single star, shown in green) would result in a Gaussian signal at the telescope.

What to Listen For

This page demonstrates wide-band (natural) and narrow-band (man-made) signals. The user selects a signal type, then uses a slider to vary the frequency of the signal.

Drake's Equation

Thie page demonstrates a simplified version Drake's Equation, an estimator of the number of communicating civilizations in the Milky Way galaxy. Three of the seven terms in Drake's Equation are shown. The user can select different values for each term. A voice announces the number of expected civilizations, and they are shown as green stars on a galaxy map. The audio and spectrometer show an imaginary composite signal from that number of civilizations.

Play the ET Search Game

The user moves a radio telescope over the sky. A few of the stars emit a narrow-band signal, representing an ETI signal; the others emit noise. The goal is to locate as many ETI signals as possible within a limited time. The game is intended to encourage the discovery of two search strategies: targeted search (looking at individual stars) and sky survey (scanning across areas with many stars).

The dynamic parts of HORSE (the sound and animation) are produced by Java applets; the static parts are HTML and images. Javascript interconnects the static and dynamic parts.

HORSE may be used for private, noncommercial purposes only. HORSE was designed as a kiosk-based exhibit for science museums. If you are interested in using it for this purpose, or if you have any problems, questions or suggestions, please mail me.

David P. Anderson
Director, SETI@home