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Space Science Reviews

, Volume 126, Issue 1–4, pp 435–445 | Cite as

Asymmetries in Mars' Exosphere

Implications for X-ray and ENA Imaging
  • Mats Holmström
Article

Abstract

Observations and simulations show that Mars' atmosphere has large seasonal variations. Total atmospheric density can have an order of magnitude latitudinal variation at exobase heights. By numerical simulations we show that these latitude variations in exobase parameters induce asymmetries in the hydrogen exosphere that propagate to large distances from the planet. We show that these asymmetries in the exosphere produce asymmetries in the fluxes of energetic neutral atoms (ENAs) and soft X-rays produced by charge exchange between the solar wind and exospheric hydrogen. This could be an explanation for asymmetries that have been observed in ENA and X-ray fluxes at Mars.

Keywords

Mars energetic neutral atoms X-rays exospheres 

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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  1. 1.Swedish Institute of Space PhysicsKirunaSweden

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