In this May 4 talk, Michael Chaffin will talk about the dynamic processes effecting Mars' atmosphere. Mars is now a desolate planet, but used to have a thicker atmosphere and flowing water on the surface. Learn about how the Sun's solar wind adversely effected Mars over time. 7:30 p.m. in the LSTB building (rm 299), located at 1234 Innovation Dr. in the CU-Boulder east campus research park. Doors open at 7 p.m. Free