Observations of Ultrafast Kelvin Wave Breaking in the Mars Thermosphere

Ultrafast Kelvin Waves (UFKWs) have been recently discovered at Mars using measurements by the Mars Atmosphere and Evolution (MAVEN) Accelerometer (ACC) instrument and the Mars Reconnaissance Orbiter (MRO) Mars Climate Sound (MCS) instrument [1]. UFKWs are eastward propagating, have a 2-3 sol period with sufficiently long vertical wavelengths to propagate into the thermosphere, and are predicted by classical wave theory to be equatorially trapped. These prior measurements characterized UFKWs at two relatively narrow altitude bands, with one measurement altitude near 80 km and a second near 150 km. Thermospheric density profiles from solar occultation (SO) measurements made by the Extreme Ultraviolet Monitor (EUVM) onboard MAVEN [2] provide a means to characterize multi-sol period waves, including UFKWs, as a function of altitude. In this study, we present first-ever observations of UFKWs as a function of altitude, including observations of rapid wave energy dissipation near 170 km indicative of wave breaking.