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116 Ideally, we would look for evidence of alien civilizations throughout the electromagnetic spectrum, over all of the sky all of the time. Unfortunately, the real world of budgets and available technologies limits our options. Researchers may be driven to searching wherever it is affordable, rather than wherever the possibilities are most intriguing. Searchers have to make choices. It remains to be seen whether they have made the right ones. “It’s naive to think that the searches we’re doing today are the best ones,” commented University of California astronomer Dan Wertheimer. Long ago, Von Hoerner counseled that it is impossible to know in advance which method is the best.” The search also will be limited by our assumptions. Searchers may have to stretch their analogies to include a wider range of phenomena. The silence we have heard so far is not in any way significant. We still have not looked long enough or hard enough. Deanl Neat. 190921 Frank White, author of The SETI Factor, suggested in 1990 that we could reach these conclusions after 30 years of searching: Our galaxy is not teeming with radio signals; there are no Type II civilizations in the Galaxy using enormous amounts of energy to communicate; our searches have detected something out of the ordinary many times, although none have been confirmed as intelligently directed signals. Lack of success so far tells us nothing, except that contact is harder than we thought it would be.” The only thing we know for sure is that our galaxy is not illuminated by powerful radio transmitters continuously broadcasting in the ways for which we have looked. Drake admitted that the negative results from Project Phoenix do imply that there are not large numbers of civilizations transmitting at many fre- quencies, at least not lately. However, there are likely to be far more intrin- sically faint civilizations than intrinsically bright ones.”* Supporters of SETI argue that it is premature to speak of a great silence. “All the world’s searches for extraterrestrial intelligence are pathetically tiny compared to the size of the radio spectrum, the width of the sky, and the depth of space,” astronomy writer Alan MacRobert declared. “Dozens of exasperated civilizations could be blasting Earth with wake-up calls at dozens of ‘logical’ hailing frequencies, and they would all likely be missed by every SETI project present or planned. Compared to the staggering job, our best SETI efforts are mere proof-of-concept trial runs.”** Sagan acknowledged that the longer we listen on the greatest variety of systems without success, it will be increasingly apparent that life that wishes to communicate with us is not an absolute cosmic commonplace (italics in Should We Continue the Search? What Can We Conclude? —Frank Drake, 19927!