Sunday, October 25, 2009

Communication with Alien Civilizations

SETI, whose job it is to find proof of alien civilizations, has yet to find any alien civilizations. The methods employed by SETI has so far focused on trying to receive messages via the EM spectrum for alien communication.

So far, SETI has been looking for messages from other alien civilizations in the form of "Anybody out there?" However, it may soon be looking for any signs of other alien civilizations by attempting "to eavesdrop on stray signs of intelligence leaked accidentally into space by other civilizations", says Steve Nadis in his Astronomy article titled Eavesdropping on E.T.: Could Changing Channels Tune Into Alien Civilizations?.

There is a quiet zone in the EM spectrum between 1 and 10 GHz. Fewer objects in the universe naturally transmit in that frequency range. If other alien civilizations know this, they may choose to intentionally transmit signals at that level. However, it may be easier to look for signals that alien civilizations naturally put out. The problem is that there is so much background noise at other frequencies, both from the Universe and Earth itself (our own civilization). Some scientists hope that a new radio-telescope coming on line in Australia called Murchison Wide-Field Array (MWA) will allow them to find anomalies that may be leaked transmissions of other alien civilizations. Though MWA is really meant to study the end of the Universe's Dark Ages (when stars began to form), it will also be able to find transient signals that may be signs that something else is out there.

Earth has been broadcasting its presence since the 1920's. Maybe another civilization has been doing the same for much longer? We will soon see.

Reference: Astronomy May 2008, Eavesdropping on E.T.: Could Changing Channels Tune Into Alien Civilizations?, by Steve Nadis

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1 comment:

Jason Hughes said...

Very interesting! Although I doubt we'll find the little green guys in our lifetime...