“Questioning Extraterrestrial Life: A Nuanced Approach”

• The Institute for Particle Physics and Astrophysics at ETH Zurich suggests the search for extraterrestrial life has not failed.

• The absence of evidence is not evidence of absence if the right questions are used.

• Bayesian analysis is used to assess habitability of exoplanets and identify potential signs of life.

• If life prevalence is low, no signs of life would be found in a sample of 40-80 exoplanets.

• The effectiveness of a search depends on the right questions, not just the number of observed exoplanets.

• Further theoretical work is needed on the theoretical side of life detection and what constitutes dispositive evidence of a habitable planet.