Of the many and various UFO / extraterrestrial-themed documents and papers that have surfaced under the terms of the U.S. Freedom of Information Act, one of the more interesting ones is Communication with Extraterrestrial Intelligence. It was written back in the 1960s (specifically in 1965) by a man named Lambros D. Callimahos. He was a cryptologist with the National Security Agency. On September 23, 1965, Callimahos took part in a panel-style debate on the subject of his paper at a conference on military electronics in Washington, D.C.
Also present for the debate was Dr. John C. Lilly, perhaps best known for his work with dolphins and in the fields of psychedelics and altered states. Others included an astronomer, Francis S.J. Heyden. The American Astronomical Society note of Heyden: " Heyden's earliest research was performed in the fields of galactic structure and variable stars. He collaborated. with Fr. L.C. McHugh S.J. in photographing star fields in the Southern Milky Way. These images were combined into an Atlas, which has become a basic reference tool for students of galactic structure." And there was a noted linguist too, Dr. Paul Garvin. The event was moderated by a Dr. Harold Wooster, at the time the Director of Information Services of the U.S. Air Force Office of Scientific Research.
Callimahos' words make for intriguing reading: "We are not alone in the universe. A few years ago, this notion seemed farfetched; today, the existence of extraterrestrial intelligence is taken for granted by most scientists. Sir Bernard Lovell, one of the world’s leading radio astronomers, has calculated that, even allowing for a margin of error of 5000 per cent, there must be in our own galaxy about 100 million stars which have planets of the right chemistry, dimensions, and temperature to support organic evolution."
He continued: "If we consider that our own galaxy, the Milky Way, is but one of at least a billion other galaxies similar to ours in the observable universe, the number of stars that could support some form of life is, to reach a word, astronomical. As to advanced (by miserable earth standards) forms of life, Dr. Frank D. Drake of the National Radio Astronomy Observatory at Green Bank, West Virginia, has stated that, putting all our knowledge together, the number of civilizations which could have arisen by now is about one billion. The next question is, “Where is everybody?”
Callimahos added: "The nearest neighbor to our solar system is Alpha Centauri, only 4.3 light years away; but, according to Dr. Su-Shu Huang of the National Aeronautics and Space Administration, its planetary system is probably too young for the emergence of life. Two other heavenly friends, Epsilon Eridani and Tau Ceti, about 11 light years away, are stronger contenders for harboring life."
He expanded, in somewhat speculative fashion, but undeniably fascinating fashion too: "Nevertheless, if superior civilizations are abundant, the nearest would probably be at least 100 light years away; therefore, it would take 200 years for a reply to be forthcoming, a small matter of seven generations. This should, however, make little difference to us, in view of the enormous potential gain from our contact with a superior civilization.
"Unless we’re terribly conceited (a very unscientific demeanor), we must assume that the 'others' are far more advanced than we are. Even a 50-year gap would be tremendous; a 500 year gap staggers the imagination, and as for a 5000-year gap… (By the way, if they are as much as 50 years behind us, forget it!) It is quite possible that 'others' have satellite probes in space, retransmitting to 'them' anything that sounds non-random to the probe. But they have probably called us several thousand years ago, and are waiting for an answer; or worse yet, they have given up; or, more probably, they have reached such impressive technological advances that they have destroyed themselves.
Callimahos turned his attentions to the kind of work that was then in place to try and find evidence of alien life: "Epsilon Eridani and Tau Ceti were the targets on which Dr. [Frank] Drake [of SETI, the Search for Extraterrestrial Intelligence] focused his attention in the Spring on 1960 in Project Ozma, an attempt to detect possible intelligent signals from outer space. The frequency selected for listening was 1420.405752 megacycles per second, or a wave length of 21 cm."
"This particular frequency, postulated independently by two professors on the faculty of Cornell University, Giuseppe Cocconi and Philip Morrison, happens to be the radiation frequency of atomic or free hydrogen which permeates space in great clouds; moreover, this frequency is within the range of radio frequencies able to pass through the earth’s atmosphere. Presumably, the significance of this frequency would be known to other intelligent beings in the universe who understand radio theory. We’re still talking about radio waves as the communication medium; other possible media might be masers, lasers, or the as yet undiscovered and unnamed 'rasers.' A technology superior to ours might even have learned how to modulate a beam of neutrinos (weightless, uncharged particles that physicists on earth find it difficult even to detect); if so, 'they' may have to wait a century or two before we learn how to build a neutrino receiver."
I'll close with these thought-provoking words from Callimahos: "...after we resolve our pressing scientific questions, it might be appropriate to make discreet inquiries as to how we could live in harmony and peace with our fellow man - that is if we aren’t eaten or otherwise ingested by the superior civilization that had the good fortune to contact us. But as far as the cryptologist is concerned, he (and generations of his descendants who might experience the supreme thrill of their lives when we hear from 'them') must keep a level head, not get excited, and be prepared to cope with problems the like of which he has never seen - out of this world, so to speak."