1. What Happened to the Ancient Martian Atmosphere? Dave Brain University of Colorado Boulder 29 July, 2015 Western Alliance Conference

2. The Martian Atmosphere Today Cold ThinToxic ++

3. Two Mysteries in One https://www.youtube.com/watch?v=zm3b3k wzSF4&feature=youtu.be

4. Up Down Where Did the Atmosphere Go?

5. What Causes the ‘Ups’? Photons Solar Wind Magnetic Field Solar Energetic Particles

6. Drivers, Reservoirs, and Escape

7. Mars Atmosphere and Volatile Evolutio N

8. Neutrals and Ions Plus Evolution IUVS NGIMS Ion-Related Properties and Processes LPW MAGSTATIC Sun, Solar Wind, Solar Storms SWIAEUV SWEA SEP The MAVEN Science Instruments:

9. IUVS Observations of Atomic Components of H 2 O and CO 2 on Their Way to Escaping

10. Expected Escape Pattern

11. Escaping Oxygen Ions

12. Close Encounter With Comet Siding Spring Breckland Skies Observatory A comet passed close to Mars on October 19, 2014

13. A Martian Meteor Shower Blue = before CSS Red = after