News Corp reported on Australia’s role in seti@home, the distributed computing program run by the University of California, Berkeley. Over 34,000 Australians donate their unused computer processing power to crunch data from radio telescopes in hopes of detecting a signal from another civilization. In between gratuitous slide shows about UFOs, the article talks to several Australians about their challenges and motivations.
But the article doesn’t spend much time on the serious nature of the Seti@Home project. Academic supercomputers are too expensive for most research projects. Scientists subscribe for time on the limited number of publicly available supercomputers just like astronomers do for time on the world’s large observatories. And just like those observatories, academic supercomputers are oversubscribed. Successful research proposals require brief processing runs, promise cutting-edge results, and offer a high chance of success.
The search for extraterrestrial intelligence, or Seti, doesn’t meet these criteria. It needs constant access to processing power, it doesn’t advance basic science, and nobody can tell whether or when the search will succeed. UC-Berkeley scientists created seti@home in 1999 to bypass academic supercomputing all together.
Seti@home uses a concept called distributed computing to take advantage of the unused computing power sitting in people’s homes. Personal computers are so powerful that they rarely use all of their performance capability. Seti@home divides data from radio telescopes - mostly the Arecibo observatory in Puerto Rico - into small chunks and distributes them to volunteers over the Internet. A screensaver-like app waits until the volunteer’s personal computer is idle and processes the data. It then uploads the results back to seti@home.
In a 2011 paper presented to the Instruments, Methods, and Missions for Astrobiology XIV conference (read it at doi:10.1117/12.894066 SPIE paywall or the free arXiv preprint), the project’s scientists reported that the seti@home distributed supercomputer averaged 3.5 petaflops - 3.5 thousand trillion calculations per second. At the time that would have made this citizen science project one of the top 3 supercomputers in the world.
Millions of people around the world have contributed to seti@home. Even though the project hasn’t found an alien signal - yet - it has detected pulsars and black holes, giving scientists extra insights into these deep space objects.