Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site lanl.ARPA Path: utzoo!watmath!clyde!burl!ulysses!allegra!bellcore!decvax!genrad!panda!talcott!harvard!seismo!cmcl2!lanl!crs From: crs@lanl.ARPA Newsgroups: net.astro Subject: Re: StarDate: March 7 Project Sentinel's Anniversary Message-ID: <23031@lanl.ARPA> Date: Fri, 8-Mar-85 09:59:33 EST Article-I.D.: lanl.23031 Posted: Fri Mar 8 09:59:33 1985 Date-Received: Mon, 11-Mar-85 05:31:25 EST References: <1065@utastro.UUCP> Sender: newsreader@lanl.ARPA Organization: Los Alamos National Laboratory Lines: 33 > Astronomers are listening with radio telescopes for signs of > extraterrestrial civilizations. More -- after this. > > March 7 Project Sentinel's Anniversary > > Today is the second anniversary of an ambitious project to look for > other intelligent life in the universe. Project Sentinel -- funded by > the Planetary Society -- is searching specific radio frequencies that > might be in use as interstellar communication channels. > > There are a vast number of such possible channels. Astronomers have > tried to narrow down their listening choices to certain plausible radio > frequencies -- ones that would be recognized and might be selected by > any technologically advanced species. One such universal channel is > the radiation frequency of neutral hydrogen atoms -- since hydrogen is > the simplest and most abundant element in the universe. Still, even if > we pick and choose, there's an enormous range of signals to check. > Is it safe to assume that what they hope to receive is a "probe" from some being that is also looking for other intelligent life? I ask because it occurs to me that frequencies such as "the radiation frequency of neutral hydrogen atoms", while attractive as a physical constant, seem to me to be as unlikely for use in everday communications by an "extra-terrestrial" as they are here on earth. Radio communication here on earth began with those frequencies that could be easily generated with frequency bands being added as technology progressed. Can anyone clarify the reasons for the frequencies chosen and, perhaps, list the bands of interest? Are "we" listening to any mundane frequencies such as those of the various broadcast bands? Perhaps they too have a Babel of rock stations! Charlie