Search Publications
Modeling Mars' ionosphere with constraints from same-day observations by Mars Global Surveyor and Mars Express
Tellmann, Silvia; Pätzold, Martin; Withers, Paul +3 more
We have analyzed a brief period of same-day observations of the Martian ionosphere using data obtained in December 2004 from the Mars Global Surveyor (MGS) and Mars Express (MEX) radio occultation experiments. These data were taken shortly after sunrise under solstice conditions in both hemispheres, with MGS in the summer (northern) hemisphere at …
Nightside ionosphere of Mars studied with local electron densities: A general overview and electron density depressions
Gurnett, D. A.; Winningham, J. D.; Frahm, R. A. +3 more
The radar sounder Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on the Mars Express spacecraft provides local electron densities from electron plasma oscillations. Here, we use the local electron densities to study the nightside ionosphere of Mars. In this study, in which local densities were sampled to a minimum altitude of…
Proton and hydrogen atom transport in the Martian upper atmosphere with an induced magnetic field
Barabash, S.; Futaana, Y.; Nilsson, H. +6 more
We have applied the Direct Simulation Monte Carlo method to solve the kinetic equation for the H/H+ transport in the upper Martian atmosphere. We calculate the upward H and H+ fluxes, values that can be measured, and the altitude profile of the energy deposition to be used to understand the energy balance in the Martian atmos…
Heavy-ion flux enhancement in the vicinity of the Martian ionosphere during CIR passage: Mars Express ASPERA-3 observations
Fedorov, A.; Barabash, S.; Futaana, Y. +6 more
A characteristic heavy-ion signature observed in the vicinity of the Martian ionosphere during passages of Corotating Interaction Region (CIR) structures in solar wind is reported. We analyzed data obtained by the IMA/ASPERA-3 onboard the Mars Express (MEX) from September to October 2007. We compared the solar wind velocity at Mars derived from a …
Dual-spacecraft observation of large-scale magnetic flux ropes in the Martian ionosphere
Gurnett, D. A.; Winningham, J. D.; Frahm, R. A. +5 more
We here report the first dual-spacecraft detection of planetary flux ropes in the ionosphere of Mars. The Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS), on board Mars Express, can measure the magnetic field magnitude near the spacecraft. Typically, these measurements track the known crustal magnetic field strength very well; …
Tracking corotating interaction regions from the Sun through to the orbit of Mars using ACE, MEX, VEX, and STEREO
Fränz, M.; Davies, J. A.; Lester, M. +3 more
We study the propagation of corotating interaction regions (CIRs) through the inner heliosphere during the solar minimum of 2007-2008 using the Advanced Composition Explorer (ACE), Mars Express (MEX), Venus Express (VEX), and the Solar Terrestrial Relations Observatory (STEREO). We present observations of 24 CIRs observed during the period from 1 …