James Green in front of a cosmis nursery background. James Green in front of a cosmic background
James Green lecture flyer


Join Dr. James L. Green as he discusses the origins and evolution of life in space and time. It is estimated that life started on Earth approximately 3.9 billion years ago. However, there are only a few locations on Earth, that old, that have remained undisturbed which would enable our study of the planetary conditions at a time that enabled life to take hold. Although we don't yet know how life got started here, early life forms would not be very complex. By studying the evolution of our own planet and Sun, it may give us some clues as to what to look for life at other locations in our own solar system and in the solar systems of other stars.

Planetary scientists have developed the capability to model how our solar system planets and sun have evolved together since their birth and what may happen to them in the distant future. Comparative planetology tells us that terrestrial planetary atmospheres have been in a process of continual change within an ever changing solar and galactic environment. We are finding some startling parallels that suggest both Venus and Mars had environments that would have been habitable for life in their distant past. New observations in the outer part of our solar system indicate that Europa and Enceladus have an ocean of liquid water beneath their icy crust in contact with mineral-rich rock. These icy moons may have the ingredients needed for life as we know it.

With these discoveries, and many others in mind, we are looking for potentially habitable exoplanets and have made some significant discoveries.

Speaker's Biography:

Jim Green worked at NASA for 42 years before retiring in December 2022. He received his Ph.D. in Physics from the University of Iowa in 1979 and worked at Marshall Space Flight Center, Goddard Space Flight Center, and NASA Headquarters. During Jim’s long career at NASA, he has been NASA’s Chief Scientist and was the longest serving director of the Planetary Science Division with the overall programmatic responsibility for the New Horizons spacecraft flyby of Pluto, the Juno spacecraft to Jupiter, and the landing of the Curiosity rover on Mars, just to name a few. He has written over 125 scientific articles in refereed journals and over 80 technical and popular articles. In 2015, Jim coordinated NASA’s involvement with the film The Martian. In 2017 Asteroid 25913 was renamed Jamesgreen in his honor.