Energetic ions in the close environment of Mars and particle shadowing by the planet


THE twin-telescope particle-detector system, SLED, aboard Phobos 2 recorded flux enhancements in the range 30–350 keV in the same general location in the close environment of Mars, over eight days at 900 km altitude in three successive elliptical orbits. Here we present possible interpretations of these observations. Energy-related particle shadowing by the body of Mars was also detected, and the data indicate that this effect occurred in <20% of the 114 circular orbits around Mars because of the nutation of the spacecraft. We discuss the influence of magnetic fields in allowing particles to reach the detector under potentially screened conditions.

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Afonin, V., McKenna-Lawlor, S., Gringauz, K. et al. Energetic ions in the close environment of Mars and particle shadowing by the planet. Nature 341, 616–618 (1989). https://doi.org/10.1038/341616a0

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