Wired reports that on March 18, the scientists behind SETI@home, the world’s largest distributed computing project, will visit the Arecibo radio telescope in Puerto Rico to re-examine the most promising 100-200 radio signals of the billions they’ve collected since beginning their search for extra-terrestrial intelligence in May 1999. Since that time, SETI@home’s 4 million participants have crunched 1.3 million years in computing time–about 1000 years per day–averaging 52 terraflops (52 trillion floating-point operations per second). The world’s most-powerful non-distributed supercomputer, Japan’s Earth Simulator, clocks in at only 10 terraflops.
According to SETI@home’s October newsletter, the most promising candidate signals must exhibit one of more of the following criteria: (1) its location matches the location of a known star, (2) its location matches the location of a known planet, (3) its barycentric frequency (in which the effects of the Earth’s spin and orbit are removed) is constant across time but cannot be attributed to RFI (Radio Frequency Interference).
So far, every signal that merits closer inspection has proven to be a red herring, so scientists aren’t getting their hopes up. “Occasionally, you find very strong signals and you look more closely, but it turns out to be a satellite or interference,” said SETI@home’s chief scientist Dan Werthimer. “We’re not jumping up and down saying we’ve got to get to the telescope immediately, we’ve just found E.T. These are the best signals that 4 million volunteers have found over the last four years, and we’re going to check up on them.”
Werthimer says that the 1.3 millions years of computing time that they’ve crunched so far is just the beginning. SETI@home has only been searching a narrow 2.5 MHz band among the billions of potential radio bands. “I’ve been doing this for 27 years and I still think we’re just scratching the surface. We’re searching such a small range of frequencies…. We are 20 or 30 years away from a thorough search. It’s like combing a cosmic haystack. We’ve just started poking around the edges.”
If they determined on April 1 that they found an actual alien radio signal, do you think they would report it or wait a day? :)
At UC Berkely, SPACE.com, New Scientist and MSNBC.
Just thought I’d share my SETI@home stats. Since Fri May 28, 1999, I’ve amassed 11.345 years of CPU time, returning a grand total of 7702 results. Anyone have that beat?
Ack! See what happens when I say I’ll finish the story when I get back from lunch?
Wow, Drog, I’m impressed with your 7000+ workunit total. I’ve only got around 850…
The rickyjames version of this story:
An early-1970s science fiction novel that made a big impression on me as a kid was The Listeners by author James Gunn, who had in turn been inspired by an earlier 1960s science book called We Are Not Alone by New York Times science editor Walter Sullivan (I wore out my copy of THAT one). Both depicted communication with aliens in a rigorously scientific manner that (unfortunately) is still accurate today: sub-light interstellar travel is extremely unlikely at best, faster-than-light travel impossible; any communication will be by radio telescope with a delay of decades between responses. Later novels like Carl Sagan’s Contact, with radioed instructions for gigantic instantaneous teleporters and ultra-photogenic Jody-Foster scientists, are unfortunately not science fiction but science fantasy.
Truth is stranger than fiction. In the 21st Century we ARE mounting a massive search for alien radio signals but in a way neither Gunn nor Sagan could have imagined. As one really big radio telescope slews endlessly across the sky on conventional radio astronomy work, the background noise is recorded and sent over the Internet to Internet SETI@Home volunteers for processing. The effort put forth has been mind-boggling. Four million volunteers have allocated 1.4 million years of continuous computer time to process over 5 billion possible alien signals. In a press release yesterday, SETI@Home sponsor The Planetary Society announced that the time for piggybacking on the astronomy efforts of others is over – at least for a few days. From March 18 thru March 20, the Arecibo radio telescope will be devoted solely to checking out the most promising 150 to 200 signals found so far over the past four years in the SETI@Home database. This re-checking effort is drawing considerable attention in the popular press and is a must to reconfirm the validity of a candidate signal. Results of next week’s effort can be monitored here; if a signal is actually confirmed, of course, you’ll certainly hear about it through the regular media once the official protocol for reciept of an extraterrestrial signal has been followed by the scientists involved. Good luck, guys and gals, and good hunting!