Search Publications
Solar Wind Induced Waves in the Skies of Mars: Ionospheric Compression, Energization, and Escape Resulting From the Impact of Ultralow Frequency Magnetosonic Waves Generated Upstream of the Martian Bow Shock
Zhang, Tielong; Futaana, Yoshifumi; Mazelle, Christian +12 more
Using data from the National Aeronautics and Space Administration Mars Atmosphere and Voltatile EvolutioN and the European Space Agency Mars Express spacecraft, we show that transient phenomena in the foreshock and solar wind can directly inject energy into the ionosphere of Mars. We demonstrate that the impact of compressive ultralow frequency wa…
Oxygen Ion Energization at Mars: Comparison of MAVEN and Mars Express Observations to Global Hybrid Simulation
Fedorov, A.; Holmström, M.; Modolo, R. +2 more
We study oxygen ion energization in the Mars-solar wind interaction by comparing particle and magnetic field observations on the Mars Atmosphere and Volatile EvolutioN (MAVEN) and Mars Express missions to a global hybrid simulation. We find that large-scale structures of the Martian-induced magnetosphere and plasma environment as well as the Mars …
Ionospheric Irregularities at Mars Probed by MARSIS Topside Sounding
Gurnett, D. A.; Halekas, J. S.; Kopf, A. J. +2 more
The upper ionosphere of Mars contains a variety of perturbations driven by solar wind forcing from above and upward propagating atmospheric waves from below. Here we explore the global distribution and variability of ionospheric irregularities around the exobase at Mars by analyzing topside sounding data from the Mars Advanced Radar for Subsurface…
Shapes of Magnetically Controlled Electron Density Structures in the Dayside Martian Ionosphere
Wild, J. A.; Kopf, A. J.; Diéval, C.
Nonhorizontal localized electron density structures associated with regions of near-radial crustal magnetic fields are routinely detected via radar oblique echoes on the dayside of Mars with the ionospheric sounding mode of the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) radar onboard Mars Express. Previous studies mostly …
Monte Carlo Simulations of the Interaction of Fast Proton and Hydrogen Atoms With the Martian Atmosphere and Comparison With In Situ Measurements
Gérard, J. -C.; Hubert, B.; Shematovich, V. I. +1 more
We present model results of the interaction of proton and hydrogen atom precipitation with the Martian atmosphere. We use a kinetic Monte Carlo model developed earlier for the analysis of the Analyzer of Space Plasmas and Energetic Atoms (ASPERA-3) Mars Express data. With the availability of Mars Atmosphere and Volatile Evolution Mission in situ m…
Precipitation of Hydrogen Energetic Neutral Atoms at the Upper Atmosphere of Mars
Kallio, E.; Barabash, S.; Futaana, Y. +3 more
We study the properties of neutral hydrogen atoms precipitating onto the upper atmosphere of Mars. Energetic neutral atoms (ENAs) are produced by the charge exchange process between protons of solar wind (both upstream and shocked) as well as planetary origins and the Martian exospheric neutrals. Using a global hybrid plasma model for Mars-solar w…
Mars Initial Reference Ionosphere (MIRI) Model: Updates and Validations Using MAVEN, MEX, and MRO Data Sets
Withers, Paul; Mayyasi, Majd; Mendillo, Michael +7 more
The Mars Initial Reference Ionosphere (MIRI) model is a semiempirical formulation designed to provide climatological estimates of key parameters of the Martian ionosphere. For the new MIRI-2018 version, an expanded database is used from the Mars Express/Mars Advanced Radar for Subsurface and Ionosphere Sounding/Active Ionospheric Sounding (MEX/MAR…
Mass Composition of the Escaping Flux at Mars: MEX Observations
Nilsson, H.; Rojas-Castillo, D.; Stenberg Wieser, G.
Using more than 7 years of ion measurements from the ASPERA-3/IMA instrument onboard the Mars Express mission, we analyze the mass composition of the two main outflowing heavy ion species O2+ and O+. Using an improved multispecies fitting technique, we discriminate the molecular from atomic oxygen ion population. W…
Influence of the Interplanetary Convective Electric Field on the Distribution of Heavy Pickup Ions Around Mars
Fränz, M.; Nilsson, H.; Liemohn, M. W. +3 more
This study obtains a statistical representation of 2-15 keV heavy ions outside of the Martian-induced magnetosphere and depicts their organization by the solar wind convective electric field (<fi>E</fi>SW). The overlap in the lifetime of Mars Global Surveyor (MGS) and Mars Express (MEX) provides a period of nearly three year…
Magnetically Controlled Density Structures in the Martian Ionosphere: Are they Stably Recurring?
Venkateswara Rao, N.; Mohanamanasa, P.; Rao, S. V. B. +1 more
MARSIS instrument aboard the Mars Express spacecraft regularly detects the magnetically controlled density structures (MCDSs) in the Martian ionosphere. In this paper, we studied the recurrence characteristics of these MCDSs using long-term (more than a decade) MARSIS observations over a selected region of 35° to 40° longitude and -10° to 10° lati…