#NatureAstronomy Insights from early life in the 3.45-Ga Kitty’s Gap Chert for the search for elusive life in the Universe https://www.nature.com/articles/s41550-025-02661-0 "Most common forms of extraterrestrial life on a rocky planet will be similar to terrestrial chemotrophic organisms which are notoriously difficult to detect and identify. An extraterrestrial observer could probably have detected any biosignature for Earth only in the last 800 Myr, even though Earth has probably been inhabited since the Hadean (4.56–4.0 Ga)."