Charles Cockell
Professor of Astrobiology, University of Edinburgh
Author: Equations of Life, Space on Earth, 
Impossible Extinction, Astrobiology: Understanding Life in the Universe

How will humanity first discover ET Life?Best guess: 
Biosignature from life in exoplanet atmosphere

Details: Biospheres produce gases and our best chance 
might be an anomalous concentration of gases in a 
distant exoplanet atmosphere, produced by microbes or 
their alien equivalent, for example oxygen or sulfur
 gases of various kinds. The search for life in the 
subsurface of Mars or in the plumes of Enceladus are good 
candidates, but three relevant points are: 
1) Exoplanet analysis will allow us to examine 
thousands of locations. Statistically, 
this gives us a better chance, 
2) We might construct telescopes to study exoplanet 
atmospheres before we can get deep into Mars or 
get plume samples from Enceladus, 
3) The request didnít specify truly alien life, 
but if we want that, then looking outside our 
Solar System to avoid life possibly related 
to life on Earth might yield earlier results.

Video that Charles Cockell contributed
Life in the Universe Pandemic Series.
A short series of lectures I recorded 
during lockdown on some thoughts about Life in the Universe:

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