A Sporadic Third Layer in the Ionosphere of Mars

Pätzold, M.; Tellmann, S.; Häusler, B.; Hinson, D. P.; Schaa, Ralf; Tyler, G. L.

doi:10.1126/science.1117755

Cited by 178 publications

(178 citation statements)

References 7 publications

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“…Since the initial work of Whitten et al (1971), progresses in laboratory measurements of ion-neutral reactions as well as radio-electric observations of the electron density profiles (Patzold et al 2005) have allowed several authors to build more detailed models of ionized species in the Martian lower atmosphere. According to Molina-Cuberos et al (2002) the most abundant ions below ∼50 km are hydronium ions H 3 O + (H 2 O) n while O + 2 dominates above ∼70 km.…”

Section: Ion Balance In Atmospheresmentioning

confidence: 99%

Applications of Electrified Dust and Dust Devil Electrodynamics to Martian Atmospheric Electricity

et al. 2016

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Atmospheric transport and suspension of dust frequently brings electrification, which may be substantial. Electric fields of 10 kV m −1 to 100 kV m −1 have been observed at the surface beneath suspended dust in the terrestrial atmosphere, and some electrification has been observed to persist in dust at levels to 5 km, as well as in volcanic plumes. The interaction between individual particles which causes the electrification is incompletely understood, and multiple processes are thought to be acting. A variation in particle charge with particle size, and the effect of gravitational separation explains to, some extent, the charge structures observed in terrestrial dust storms. More extensive flow-based modelling demonstrates that bulk electric fields in excess of 10 kV m −1 can be obtained rapidly (in less than 10 s) from rotating dust systems (dust devils) and that terrestrial breakdown fields can be obtained. Modelled profiles of electrical conductivity in the Martian atmosphere suggest the possibility of dust electrification, and dust devils have been suggested as a mechanism of charge separation able to maintain current flow between one region of the atmosphere and another, through a global circuit. Fundamental new understanding of Martian atmospheric electricity will result from the ExoMars mission, which carries the DREAMS (Dust characterization, Risk Assessment, and Environment Analyser on the Martian Surface)-B R.G. Harrison

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Section: Ion Balance In Atmospheresmentioning

confidence: 99%

Applications of Electrified Dust and Dust Devil Electrodynamics to Martian Atmospheric Electricity

et al. 2016

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“…The Martian ionosphere, formed by the photoionization of the major neutral constituents CO 2 and O with subsequent molecular reactions creating O 2 + as the major ionospheric ion species and O + becoming comparable at altitudes ≥300 km, was extensively studied by radio occultation measurements (Kliore, 1992;Mendillo et al, 2004;Pätzold et al, 2005), radar remote sounding (Gurnett et al, 2005, in-situ measurements by retarding potential analyzer (Hanson et al, 1977;Hanson and Mantas, 1988) and 'plasma wave diagnostics' (Gurnett et al, 2005. Since Mars is not screened by a large-scale magnetic field the solar wind has direct access to the ionosphere providing momentum and energy transfer to the upper layers of the ionospheric plasma.…”

Section: Introductionmentioning

confidence: 99%

Upper ionosphere of Mars is not axially symmetrical

et al. 2012

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The measurements carried out by the ASPERA-3 and MARSIS experiments on board the Mars Express (MEX) spacecraft show that the upper Martian ionosphere (h ≥ 400 km) is strongly azimuthally asymmetrical. There are several factors, e.g., the crustal magnetization on Mars and the orientation of the interplanetary magnetic field (IMF) which can give rise to formation of ionospheric swells and valleys. It is shown that expansion of the ionospheric plasma along the magnetic field lines of crustal origin can produce bulges in the plasma density. The absense of a magnetometer on MEX makes the retrieval of an asymmetry caused by the IMF more difficult. However hybrid simulations give a hint that the ionosphere in the hemisphere (E − ) to which the motional electric field is pointed occurs more inflated than the ionosphere in the opposite (E + ) hemisphere.

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“…This presentation concerned the effects of solar flares and meteors on the Mars ionosphere [Pätzold et al, 2005;Mendillo et al, 2006]. Both of these processes increase plasma densities in the bottomside ionosphere at altitudes of about 90 kilometers.…”

Section: Oral Sessionsmentioning

confidence: 99%