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43 SETI astronomers might see alien beamed communications—espe- cially those not meant for us—as flashes of energy that dim within seconds. SETI has focused on continuous or repeated signals such as radio beacons because transient signals are more difficult to pick up, and much tougher to find a second time. “Our present systems are very ineffective in dealing with transient signals,” said Drake." New observ- ing technologies will have enhanced abilities to record very brief signals. In the meantime, the technology for radio searches continues to improve. The Arecibo telescope has been upgraded, raising its highest usable fre- quency while lowering system noise. Radio astronomers are planning more powerful instruments, although these are not dedicated to SETI. First would be an expansion of the Very Large Array of radio telescopes in New Mexico, to be completed by 2010. The Square Kilometer Array that may be built by 2015 could have 50 to 100 times the sensitivity of any existing array. Also on the agenda is a Low Frequency Array.** Experts meeting with SETI Institute sponsorship recommended devel- oping and building a One Hectare Radio Telescope, using a phased array of many small dishes for surveys in the galactic plane. This could be a prototype for the Square Kilometer Array. The group also recommended building and operating an Omnidirectional SETI System, an all-sky, all the time microwave search for transient beacons. In addition, these experts called for support of optical searches for rapid pulses and data mining of existing records for optical signals. The estimated annual cost of the rec- ommended programs was 8 million dollars per year.* Meanwhile, computer technology for data processing is improving rapidly. Given the continuing reduction in computation costs, said SETI Institute astronomer Seth Shostak, we can expect that the speed of the reconnaissance will double every 18 months.” Radio astronomers face increasingly serious interference from satellite and terrestrial transmitters. The 1982 SETI petition pointed out that, because of the growing problem of radio-frequency interference, the search will become more difficult the longer we wait. If we do not protect certain wavelengths from interference, said Bernard Oliver, we may doom human- ity to galactic isolation. Advancing technology may have changed the game. Chyba declared in 1996 that searches had reached a level of technical maturity where all interference can be recognized and excluded.*° SETI researchers have studied space-based observing systems that could open up new opportunities at frequencies that cannot be observed from the Earth’s surface. Unfortunately, the high cost of such observatories makes early implementation unlikely. Horowitz proposed an interim step that resembles SERENDIP: adding a SETI component to a planned NASA mission, the Terrestrial Planet Finder.” Privatizing SETI