Although as of this writing the SETI (Search for Extraterrestrial Intelligence) program has had funding problems, its use of mathematics in seeking intelligent life on other planets has always been fascinating. Large computers at several facilities, including the University of California at Berkeley, analyze data from various radio telescopes in real time (including at Arecibo in Puerto Rico), seeking out data that could be indicative of an alien civilization. Because of the large number of personal computers currently in use around the globe, SETI researchers have enlisted help from the public to seek out new civilizations. A program can be downloaded to private computers and used to run data in the background while the computer user works on other programs; the results are then automatically transmitted to SETI researchers.

Overall, a computer program looks at a large slice of the electromagnetic spectrum—a band 100 MHz (megahertz) centered around 1420 MHz. (It does this by performing a variety of digital signal processing operations on radio frequency data, translating the information using a special algorithm.) This part of the spectrum is where scientists predict an “advanced civilization” would most likely be sending out a signal, concentrating the message’s power in one narrow frequency range, and if the signal strength gets higher that might be evidence of an extrasolar civilization.