WORLD SCIENCE

"Long before it's in the papers"
June 21, 2005

News reports of signal from alien life off-base, scientists say

Sept. 2, 2004
Special to World Science

A rash of recent news reports about the detection of a possible signal from alien life forms is “highly exaggerated,” said the scientist who was originally quoted as the key source of the news.

The slew of reports began when New Scientist magazine published a story on Wednesday about the most promising signal detection to date of the SETI@home program. The program is a scientific project that allows home computer users to donate part of their computers’ processing power toward helping the search for extraterrestrial civilizations.

“As of now there is no breakthrough,” said an announcement Thursday on the website of the The Planetary Society, a space advocacy group. The website quoted SETI@home Chief Scientist Dan Werthimer of the University of California at Berkeley saying the reports were “highly exaggerated.”

The magazine reported that SETI@home had found its most promising signal to date, and discussed its possible origins. But the Planetary Society announcement said the reports should be taken with a grain of salt.

“Like all of SETI@home’s 5 billion potential signals, this candidate, labeled SHGb02+14a, was assigned a numerical score representing the statistical likelihood that it is indeed an intelligent extraterrestrial signal. Its relatively high score placed it among the 200 ‘top candidates’ selected for the targeted reobservation sessions.”

During later reobservations, this signal was “one of the very few to be confirmed during the reobservations, and the only one whose score following the sessions actually went up.”

But “the chances that it actually represents an intelligent signal from beyond remain extremely slim,” the announcement added.

The statement continued as follows. 

“Chance alone would make it probable that at least one of the billions of candidates detected by SETI@home would be observed on three separate occasions, as was the case for this candidate. Furthermore... the fact that this candidate’s frequency drifts rapidly makes it extremely improbable that it is a transmission from extraterrestrials. Because of the drift, explained Werthimer, ‘if we had looked at the sky even a few seconds later we wouldn’t have found a match’ for this candidate. A signal that drifts so quickly that it can only be heard for seconds at a time at a given frequency can only be detected by blind luck. Needless to say, such a transmission is an unlikely vehicle for message from an advanced civilization…

“Around the world, millions are still crunching SETI@home data on their personal computers. The Search for extraterrestrial intelligence continues at full speed.”

—EJL

WORLD SCIENCE

WORLD SCIENCE