Indeed.
Posted on 03/28/2004 8:38:01 AM PST by Momaw Nadon
Astronomers have completed their most sensitive search yet for radio signals from intelligent life in space.
They believe the best way to find ET is to look for a radio signal. Such signals can travel vast distances.
The Arecibo radio telescope in Puerto Rico, supported by Jodrell Bank, searched over a period of 10 years.
The scientists looked at 800 nearby stars with no evidence of a signal from ET. They say they have learned a lot, and plan another search next year.
From the ashes
The last star scrutinised by Project Phoenix - the most powerful search for intelligent life in space ever carried out - was HD 169882, a fairly ordinary star lying just 88 light-years away.
The result was that no signals indicative of an intelligent origin are coming from it, at least during the time it was observed.
So if there are any aliens on a planet circling that star then perhaps they are not interested in signalling, or are doing it in a way we cannot yet detect.
Project Phoenix was so-named because it rose from the ashes of a US space agency (NASA) initiative to search for intelligent life in space that was cancelled by US Congress in 1993.
Despite this setback, the scientists involved were determined to carry out their search.
"When the 'termination' order came from Washington, most of the equipment was on lab benches. We were immediately faced with three challenges: raise private money, get NASA to loan us the equipment and get it working," Peter Backus, project manager for Phoenix, told BBC News Online.
After the initial scramble, the scientists managed to get an Extra-Terrestrial Intelligence (ETI) search system built and used it on the Parkes radio telescope in Australia in February 1995, just one month later than the original Nasa plan.
No signal
Much of Project Phoenix's time was spent on the world's largest radio telescope, the 330-metre dish at Arecibo, which takes advantage of the natural topography of Puerto Rico's mountains.
"Over the years we have observed about 800 nearby stars over billions of frequency channels at high sensitivity," says Backus.
"No other search covered as many frequencies or achieved the same sensitivity. It was the only search capable of detecting ET transmitters with power comparable to our own military radars."
One of the problems in looking for signals from intelligences in space is that signals from Earth can interfere, so the scientists have to have a reliable way of discriminating between ET and terrestrial interference.
Phoenix pioneered a technique of "real-time interference monitoring" using a second radio telescope to determine if any suspicious signal was actually coming from deep space.
Expanded search
No suspicious signal survived that test, but the astronomers are not down-hearted; they know that ET could be detected tomorrow, in a thousand years, or never.
They say a search with an outcome that could be one of the biggest scientific discoveries of all time is worth the effort.
"We've learned a lot about searching for Eti. We'll carry those lessons and the new search system to the Allen Telescope Array (ATA)," Backus adds.
"Later this year, we'll be using the ATA with 32 small dishes. As the array expands, we'll start a new targeted search covering several hundred thousand stars.
"As I look back over the past 10 years I'm very proud of what we have achieved - the most sensitive and comprehensive search of our galactic neighbourhood.
"Conclusion: we live in a quiet neighbourhood."
800 out of uncountable *billions* of star systems.
Exactly. In fact, by the use of FFTs, many narrowband frequencies are scanned simultaneously. They are also checked for a doppler shift due to planetary motion.
To escape detection, an advanced species would send out Doppler-shift-proof signals. (But I can't imagine how they'd manage that trick.) Well, maybe they'd only send out very brief signals at the same time each day. You'd never see a difference.
Indeed.
Indeed you are. :-)
Except our planet is rotating as well. :-)
Not only is SETI privately funded and far bigger than the crappy little federal program it replaced, but it is producing so much radiotelescope data that a whole new computational form, grid computing, had to be developed to reduce the data. This technique, setting millions of scattered PC's to work on small chunks of the data set, is now being applied to similar problems like protein folding. If you don't like lending the spare cycles on your PC to SETI, you can apply it to cancer research.
I believe there are much more civilizations than you estimate. It is entirely possible that advanced civilizations may be beyond radio as a means of communication, or use a different method altogether .
I saw a TV science show a few years ago theorizing that someday soon (a few hundred years?), we will be a silent planet, no broadcasting of any kind, all communication similar to cable or fiber optics.
This may be off topic, but for the past several decades sightings of aerial phenomena have been reported, have any communications ever been reported?
(Looks like a ping is needed for Quix's comments.)
You HAVE GOT to be kidding. Wherethhell have you been? THEY ARE HEE ALREADY, DOOFUS
Well, that would affect any signal you get, artificial or otherwise.
YOU'RE too modest, RA.
Your comment is worth at least $0.05.
I'd say bathing ought to be the first priority.....
;-)
Unless our antennae were located at the poles, or the target star system lies on a line parallel to our polar axis
;-)
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