Exoplanet Occultations as Technosignature Targets

Abstract

Recent SETI surveys have increased the fraction of the cosmic haystack that has been analyzed by focusing on increasing the number of studied target systems and the total time each target is observed. However, few of these surveys have considered when is best to observe their targets; often instead relying on the assumption that technosignature targets are persistent and detectable over long timeframes. While several time-based search considerations exist within the SETI literature, relatively few have been further investigated nor used. However, advancements in our ability to detect and characterize exoplanets and their orbital dynamics give us an opportunity to search for technosignatures originating from exoplanets that have the solar system in their own transit zones. Inspired by the signals sent and received by the Deep Space Network, we present a method to eavesdrop on spillover communications by identifying when two or more exoplanets are collinear with Earth, a scenario known as a planet-planet occultation. This strategy is sensitive not only to deliberate transmission attempts, the subject of most SETI searches, but also to communications not intended for Earth.

Evan L. Sneed

he/him or they/them

Human searching for life far from home & improving habitability on Earth