Mars today is a global cold and dry desert, but many landforms across its surface look conspicuously similar to river valleys, deltas, and alluvial fans on Earth. Join Center for Earth and Planetary Studies scientist Alexander Morgan as he uses data returned from robotic spacecraft, computer modeling, and field work to piece together the history of water on the Martian surface.

Meet at the Museum "Great Seal", in the Boeing Milestones of Flight Hall on the first floor.

About the Ask an Expert lecture series: Every Wednesday at noon in the National Mall Building, a Museum staff member talks to the public about the history, collection, or personalities related to a specific artifact or exhibition in the Museum.