1,1,3- 1Mullard Space Science Laboratory, University College London, Dorking, United Kingdom (d.verscharen@ucl.ac.uk)
- 2Laboratoire de Physique des Plasmas, Ecole Polytechnique, Palaiseau, France (matthieu.berthomier@lpp.polytechnique.fr)
- 3Space Park Leicester, University of Leicester, Leicester, United Kingdom (bscmdr1@leicester.ac.uk)
The Mars Electron Analyser System (M-EAS) is a top-hat electrostatic analyser for the in-situ detection of electrons. It is part of the Mars Ensemble of Particle Instruments (M-EPI) suite on both M-MATISSE spacecraft. Through the combination of electrostatic energy selection and electrostatic angular deflection, M-EAS samples incoming electrons in energy, azimuth, and elevation bins. In this way, M-EAS records the full 3D velocity distribution function of the electrons at high cadence. This observation allows M-EAS to measure the properties of the electrons encountered by M-MATISSE. Moreover, M-EAS observes the pitch-angle distribution of photo-electrons from Mars, which enables the determination of the magnetic connectivity between the spacecraft and the planet's ionosphere. M-EAS also measures negative ions that result from photo-chemical processes in Mars' upper atmosphere. In this presentation, we will summarise the science drivers and present the instrument design for M-EAS.
How to cite: Verscharen, D., Coates, A., Brockley-Blatt, C., Darnley, R., Nicolaou, G., Berthomier, M., and Sanchez-Cano, B.: The Mars Electron Analyser System (M-EAS) on board M-MATISSE, EPSC-DPS Joint Meeting 2025, Helsinki, Finland, 7–12 Sep 2025, EPSC-DPS2025-895, https://doi.org/10.5194/epsc-dps2025-895, 2025.
