Screensaver continues the search

Computers all over the world have found a new task when their owners are not putting them to use: SETI@Home — a screensaver that doubles as the largest supercomputer on Earth.

When the screensaver is installed, a package of data (about 500 kilobytes) is downloaded from the project server of Search for Extraterrestrial Life. Then an amount of time is set, after which the program starts when the computer is idle.

The program then starts analyzing data. Once it has finished, it sends the data back to the SETI server and requests a new one.

The program is searching for patterns in the signals recorded at the Arecibo radio telescope in Puerto Rico, the biggest of its kind.

The idea is that only planets with intelligent life would emanate such signals. The search is also displayed on screen in an interface that pays tribute to Star Trek: The Next Generation.

Since its inception in 1999, millions of users have found this a worthy cause to which to donate the processing power of their computers when they are not in use. The distributed computing project has made history as the largest ever attempted, as 4 million computers are crunching numbers in 226 countries, totaling a cumulative 1.3 million years in computing time toward the search for extraterrestrials.

The system has also grown to become the largest supercomputer on Earth. Its 52-trillion-floating-point-operations-per-second system makes it five times larger than the next biggest, a 10-trillion-per-second system in Japan, and more powerful than all supercomputers, including the one in Japan, combined.

Recently, SETI scientists decided to return to Puerto Rico and check some of the 5 billion signals that have been analyzed through the years by the screensaver.

Originally scheduled to occur between March 18 and 20, the project had to be moved back a few days to make room for other scientists who were observing eruptions on our sun and should now be completed by the end of the week.

The SETI scientists are checking some signals that have what they call the “wow” factor. This feature designates how often they have been witnessed as periodic signals during the course of 18 months.

Most of these signals have been ruled out as either satellites or other background noise, but the search has continued unabated. So far, only 500 stars of the set goal of 1 million have been analyzed, so the search will continue for at least another 20 to 35 years.

SETI@Home can be downloaded free for a wide variety of operating systems from SETI’s Web site.

http://setiathome.ssl.berkeley.edu