Page Content (OCR)
363 undesirable reactions by humans. If the aliens showed hostile intent, the U.N. Security Council would decide on defensive measures. Schenkel already had proposed new declarations of principles, one of which addressed the landing scenario.” Margaret Race of the SETI Institute found that these efforts, modest though they may be, are unusually forward-looking. Within the context of different types of searches for extraterrestrial life, the SETI community was alone in having conducted serious international discussions of how to respond to a detection. Although the Declaration of Principles does not address every issue, it is the only organized attempt to codify guidelines and policies. By contrast, there is no clear guidance on what to do if and when nonintelligent extraterrestrial life is found.'® False alarms about possible impacts of asteroids on the Earth revealed that no guidelines existed for who should have been informed when, or what emergency measures should have been taken, such as issuing a public warning. This led to the adoption in 1999 of what is known as the Torino Scale for impact risk, based on the probability of impact and the size of the impactor. Some initially worrisome predictions about close encounters with aster- oids raised questions about putting out undigested information. An observer participating in the Lincoln Near-Earth Asteroid Research program posted possible orbits for minor planets without noticing that one of them might have a one in four chance of hitting the Earth within days. A flurry of Internet communications led to further observations showing that this body would miss us. Concerned about future premature announce- ments of astronomical phenomena, the Central Bureau for Astronomical Telegrams may place more emphasis on confirmation by independent observers.'” That is likely to mean a delay. Similar approaches have been suggested for contact with extraterrestrial intelligence. Donald Tarter, assuming the remote detection scenario, suggested that a suspected extraterrestrial signal be examined for five characteristics: certainty of extraterrestrial origin; clarity of signal con- tent; sensory accessibility; activity level demanded of the recipients; intentionality.” In 2000, Ivan Almar and Jill Tarter proposed a scale for classifying the impact of discovering extraterrestrial intelligence. Factors include the class of phenomenon, ranging from traces of astroengineering to an Earth- specific message; the type of discovery—the result of SETI or some other kind of observation, or a re-evaluation of archival data; distance, from Rating the Impact Rating the Impact