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SETI: the Role of the Dedicated Amateur

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SETI: the Role of the Dedicated Amateur terrestrial beings. Given that no human effort can impact this particular factor, : what can we do to maximize our chances SETI for SETI success? For a brief time (admittedly a mere eyeblink in human history), the govern- ments of planet Earth threw their prestige The Role of the and fiscal resources at the SETI problem, sponsoring any number of scientific searches. But it is amateurs who have made, and continue to make, the most sig- nificant strides toward contact. Dedicated Amateur An amateur, as defined by science and the Olympics Committee alike, is one Dr H. Paul Shuch, N6TX who strives to excel without financial compensation. The motivation of the ama- teur is revealed by the Latin root of the word: an amateur works for love. Ask any contemporary SETI scientist The Search for Extra-Terrestrial Intelligence or technologist why he or she strives against incredible odds. The answer is al- is moving forward on a number of fronts, ways the same. What modest salary he or she may draw is almost incidental. Any thanks in large part to amateurs who skilled SETIzen could always make more money by diverting the requisite effort in volunteer their time and expertise. a different direction. It is indeed for the love of the game that the best and the brightest choose to compete in the SETI Olympiad. ince its emergence as a respectable interpretation. Like the amateur scientific discipline nearly a half athlete competing in an Olympiad, the The Athletes century ago, the electromagnetic amateur SETIzen can expect to struggle Not all SETI pioneers are licensed ra- Search for Extra-Terrestrial Intelli- for survival, absent commercial or insti- dio amateurs (though those I will discuss Sgence (SETI) has been dominated by tutional sponsorship. Grassroots amateur here are, or were). Not all of the work three classes of practitioners: government efforts can nevertheless supplement the described here was pursued as a strictly agencies, academic institutions, and non- accomplishments of the professional amateur endeavor (though some of it profit organizations surviving on a com- SETI community, bringing us all closer was). What these SETI players share is bination of private contributions and to the day of Contact. the spirit of amateurism that marks their research grants. Recent technological ad- science as being of truly Olympian stat- vances have brought a new group of play- The SETI Olympiad ure. These representative examples, by no ers into the SETI game—dedicated The challenge of interstellar contact, means inclusive, show how the world’s amateurs with a personal passion for no less elusive than the quest 50 years ago dedicated radio amateurs competed, and achieving interstellar contact. to break the four-minute mile, is continue to compete, for SETI glory. This article explores the contributions demanding of human skill and persever- such nonprofessionals are making to ance. Unfortunately, success in this par- Grote Reber, W9GFZ SETI science, in the realms of experimen- ticular arena is also a function of one When the Father of the Radio Tele- tal design, equipment construction, soft- significant factor beyond human control: scope (SK, December 20, 2002) built the ware development, direct observation, the very existence, in the proper time- world’s first modern radio telescope in sky coverage, signal analysis and message frame, of technologically advanced extra- 1937, a 10-meter-diameter parabolic re- A roomful of interested amateurs share insights and ideas at one of The SETI League’s annual SETICon Technical Symposia. Dr Malcolm Raff, WA2UNP, assembles a low-noise microwave preamplifier at a SETI League Hardware Workshop. Reprinted with permission; copyright ARRL. September 2005 43 COURTESY VE3MDL SETI League member Marcus Leach, VE3MDL, built his own software-controlled receiver for wideband SETI scanning. SETI League members use a variety of digital signal processing software tools to examine candidate signals in the time and public as Kent Clark, the character based frequency domains. upon him in the popular film Contact. The first (and probably still the only) blind in- dividual to earn a PhD in the highly vi- flector in the backyard of his mother’s John Kraus’ grad student Bob Dixon, sual discipline of astronomy, Kent house in Wheaton, Illinois, he was work- W8ERD, succeeded him as Director of developed the signal detection algorithms ing strictly as an amateur, and under the the OSU Radio Observatory. Dixon is for the late NASA SETI program, and authority of his ham radio license. Grote now leading a team of dedicated amateurs later for The SETI Institute’s Project Phoe- produced the first radio map of the Milky in the design of the omnidirectional Argus nix targeted search. If he has seen farther Way Galaxy, though it took years for his radio telescope. than other men, it is because Kent Cull- amateur accomplishments to gain accep- ers stands on the shoulders of some very tance from the world’s astrophysics pro- Paul Horowitz, W1HFA clever code. fessionals. His subsequent low-frequency Still active on the Amateur Radio radio astronomy research from Tasmania bands, a passion he has pursued since Seth Shostak, N6UDK continued in the amateur tradition of in- childhood, Horowitz heads Harvard Seth’s face is familiar on television, dependent research for its own sake. University’s SETI efforts, and designed and his voice a fixture on broadcast ra- Never one to shy away from controversy, the Project META and BETA searches dio, in his professional role as public pro- Reber’s last published paper was titled funded in part by the Planetary Society. grams scientist for the SETI Institute. That “The Big Bang is Bunk!” He is the author of the world’s most popu- voice is less often heard on the ham radio lar Electronics Engineering undergradu- bands, but it is there that Shostak first Phil Morrison, W8FIS ate textbook. Lately he has been turning gained exposure to the technologies he Undeniably one of the patriarchs of his interests and expertise toward Opti- routinely exploits as a senior SETI scien- SETI, Professor Morrison had long since cal SETI. tist. He encouraged The SETI League in gone inactive on the ham bands when in the construction and testing of its W2ETI 1959 he coauthored the first serious sci- Kent Cullers, WA6TWX Microwave Moonbounce Calibration entific SETI paper. His boyhood interest A world-class leader in digital signal Beacon, and was the first radio amateur in Amateur Radio had motivated his in- processing, Cullers is better known to the to detect its weak signals reflected off the terest in exploring the feasibility of mi- lunar surface (albeit with the 305-meter- crowaves for interstellar communication. diameter Arecibo Radio Telescope). During SETI’s Golden Age he has in- spired a whole generation of engineers Richard Factor, WA2IKL and scientists. On a personal note, my own If SETI is truly the science that refuses SETI interests were motivated by follow- to die, that is due in large part to this New ing in Phil Morrison’s footsteps (albeit Jersey industrialist. An active ham since from a distance of 30 years). As an EE boyhood, Factor was dismayed at Congres- undergraduate at the Carnegie Institute of sional cancellation in 1993 of the NASA Technology, I had the privilege of oper- SETI program. Then, putting his money ating W3NKI, the campus ham radio sta- where his mouth is, he founded the non- tion he had founded three decades prior. profit SETI League, to involve the world’s radio amateurs in privatizing the search. John Kraus, W8JK Though not as active as he would like to be Arguably the most creative antenna in Amateur Radio astronomy, Factor’s designer of his generation, Kraus (SK, greatest contribution has been his leader- July 18, 2004) is best remembered for the ship role as SETI League president and pri- late Big Ear radio telescope that he de- mary source of financial support. He can signed and built at Ohio State University. Dr John Kraus, W8JK, was an inspiring claim much of the credit for the 126 Ama- teacher, prolific author, prominent Big Ear conducted the longest running antenna designer and one of the fathers teur Radio telescopes that SETI League continuous SETI sky survey in history. of modern radio astronomy. members now operate all over the world. 44 September 2005 The Organizing Committee cess them in a suitable microwave re- Founded by Richard Factor in 1994 as ceiver. Amateur Radio astronomers have a response to the demise of the NASA modified military and government surplus SETI program, The SETI League, Inc is equipment, employed commercial receiv- a grassroots Amateur Radio club of glo- ers produced for the ham radio and tele- bal scope and galactic span. It coordinates communications markets, and, more the SETI activities of 1450 experiment- recently, designed their own dedicated ers in 66 countries on six continents. Its SETI receivers from scratch. Every year members design hardware and software at its SETICon Technical Symposium, for a coordinated all-sky survey, publish The SETI League hosts a microwave cir- articles, conduct conferences, construct cuit construction workshop, to train its and operate equipment, and collectively members in the skills necessary to pro- control more radio telescopes than exist duce a workable hydrogen line receiver. in the rest of the world, combined. Funded entirely by membership dues and The Binathalon individual contributions, The SETI The output of the typical microwave League currently has no paid employees, receiver is analog baseband, generally in with all its functions being performed by the audio range. This signal is converted volunteers. The SETI Horn of Plenty, a waveguide to a string of binary digits for signal analy- horn antenna for 1.3 to 1.7 GHz designed sis, often in a personal computer sound The SETI League’s main medium of by the author, has been duplicated by communications is its extensive Web dozens of SETI League members around card.
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