Strategies for the Detection of ET Probes Within Our Own Solar System

Abstract: Arguments are reviewed in support of the hypothesis that ET would more likely send physical probes to surveil our Solar System and communicate with Earth than to communicate from afar with interstellar radio, infrared or laser beacons. Although the standard SETI practice of targeting individual stars or galaxies with powerful telescopes might detect a foreground local probe by serendipity, an intentional hunt for those probes would entail a different set of strategies, most notably sacrificing sensitivity (needed to detect a very faint and very distant signal) in exchange for a widened field-of-view (because a local signal can be reasonably hypothesized to be relatively bright). This paper suggests a number of strategies to detect local ET probes.