2015/07/30 by Adam Stevens, Duncan Forgan, Jack O'Malley-James +1 · 2 voices · 29 citations
Earth and Planetary Sciences · Physics and Astronomy · #Earth Systems and Cosmic Evolution #Exoplanet #Gamma-ray bursts and supernovae #Milky Way #Observable #Search for extraterrestrial intelligence #Signature (topology) #Space Science and Extraterrestrial Life #Variety (cybernetics) #astro-ph.EP
paper · pdf · doi:10.1017/s1473550415000397
published in International Journal of Astrobiology 15(4), 333-344 (Cambridge University Press) · 35 pages, 2 figures, accepted for publication in the International Journal of Astrobiology
arxiv created 2015/07/30 · openalex publication_date 2015/10/23 · openalex created_date 2016/06/24 · arxiv updated 2020/12/16 · openalex updated_date 2026/08/05
We address the possibility that intelligent civilisations that destroy themselves could present signatures observable by humanity. Placing limits on the number of self-destroyed civilisations in the Milky Way has strong implications for the final three terms in Drake's Equation, and would allow us to identify which classes of solution to Fermi's Paradox fit with the evidence (or lack thereof). Using the Earth as an example, we consider a variety of scenarios in which humans could extinguish their own technological civilisation. Each scenario presents some form of observable signature that could be probed by astronomical campaigns to detect and characterise extrasolar planetary systems. Some observables are unlikely to be detected at interstellar distances, but some scenarios are likely to produce significant changes in atmospheric composition that could be detected serendipitously with next-generation telescopes. In some cases, the timing of the observation would prove crucial to detection, as the decay of signatures is rapid compared to humanity's communication lifetime. In others, the signatures persist on far longer timescales.