A Low Upper Threshold For Saltation-Mediated Triboluminescence At Gale Crater, Mars H. M. Sapers1, J. L.
Kloos2, M. Baker3, D. M. Fey4, H. Kalucha5, M. Lemmon6, M. Minitti7, C. Newman8, J. E. Moores1, 1york University Centre For Research In Earth And Space Science (Hsapers@Yorku.Ca), 2university Of Maryland, 3smithsonian
Institution, 4malin Space Science Systems, San Diego, Ca 92191-0148, Usa 5california Institute Of Technology,
Division Of Geological And Planetary Sciences, 6space Science Institute, 7planetary Science Institute, 8aeolis Research

Introduction: Laboratory Studies Suggest That Saltation-Driven Grain-To-Grain Collisions Are Capable Of
Producing Triboelectric Discharge In The Hyperarid,
Near-Surface Atmosphere On Mars 1,2. Saltation Simulation Experiments Induced Triboelectric Discharge With A
Radiance Of Approximately 1.4 - 3.2 Μw/M2/Sr Under A
Simulated Martian-Atmospheric Composition At 8 Mbar
Pressure - Capable Of Ionizing Methane And Providing A
Potential Mechanism To Explain The Enigmatic Seasonal
Variations Of Ch4 And O2 3. With Observational Evidence Of Wind-Mediated Saltation 4–7, Saltation-Induced
Triboelectric Discharge Is Theorized To Be Common On
Mars, But Has Yet To Be Observed In Situ. We Successfully Carried Out The Fist In Situ Triboelectric Observations Carried Out By The Mars Hands Lens Imager
(Mahli) Onboard The Mars Science Laboratory
(Msl) Curiosity Rover Setting An Upper Threshold For
Triboelectric Discharge That Would Not Have A Measurable Effect On Near-Surface Atmospheric Composition.
The Observed Seasonal Variation Of Ch4 And O2 In
The Martian Atmosphere Is Not Fully Explained By Currently Understood Atmospheric Or Geological Processes.