Paul Hertz
Director of Astrophysics: NASA (since 2012)
Chief Scientist: NASA’s Science Mission Directorate (previously)
Ph D.: Astronomy: Harvard University (1983)
Author: Over 100 refereed science papers
(involving every electromagnetic band from radio to gamma-ray)

How will humanity first discover ET Life?

Best guess: Biosignatures (distant exoplanets)

Life will be found first on an exoplanet, not in the Solar System 

About Life
Not a rare process
Arose rapidly on Earth after conditions were right
Should arise in some reasonable fraction of other places, when conditions are right

Where can life be found?

Solar System  
Only 2 or 3 places where conditions might have been appropriate for life to arise in our Solar System the last 4 billion years 
Unless life is likely in appropriate conditions, Earth is the only place in our Solar System where life developed 

Distant Exoplanets
10-20% of Sun-like stars have Earth-like planets in the habitable zone	
Around a billion potential sites for life to arise on an exoplanet likely exist in our galaxy alone
NASA is involved in the development of technologies, mission concepts, and observatories to find life on these exoplanets

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