Technosignatures in the Thermal Infrared

Abstract: WISE, Gaia, and JWST provide an opportunity to compute the first robust upper limits on the energy supplies of extraterrestrial civilizations, both for stars in the Galaxy (Kardashev Type II civilizations) and for other galaxies (Kardashev Type III civilizations). Together, they allow for a nearly-complete catalog of nearby stars with infrared excesses, which is valuable for both stellar astrophysics and searches for technosignatures; and of the MIR luminosities of galaxies, important for studies of galaxies' star and star-formation properties, but also for the identification of potential galaxies endemic with alien technology. JWST will provide the crucial mid-infrared spectroscopy necessary to identify the origin of these infrared excesses, advancing both traditional astronomy and searches for technosignatures. Such signatures are distinguished from dust by their lack of far-infrared emission and lack of association with star formation.