An American astrophysicist and former NASA Chief Scientist, Jim Green has been a leader in shaping scientific thinking about the planet Mars. He advocates the idea that ancient Mars may have once been habitable, with a thicker atmosphere, surface water, and a global magnetic field capable of supporting life. In 2015, he coordinated NASA’s involvement with the Ridley Scott film The Martian. 

In his distinguished 42-year career at NASA, Dr. Green was the longest serving director of NASA’s Planetary Science Division with overall responsibility for 31 NASA missions, and contributions on other Agency missions. 

He received NASA’s Exceptional Achievement Medal and the Distinguished Service Medal.  In 2017, Asteroid #25913 was renamed Jamesgreen in his honor. 

He is co-author of the book Mars: Photographs from the NASA Archives.