Introduction: The close encounter of Comet C/2013 A1 (Siding Spring) with Mars on 2014 Oct 19 generated a lot of interest and modelling work [1] [2] [3] in the solar system community. A press release from NASA implied that a meteor shower was detected on Mars by their space instruments some hours after the comet-Mars close encounter. Various work [4] [5] [6] has suggested that very specific meteoroid sizes and ejection conditions may be required to produce meteor phenomena at Mars at the given times.
Dynamics: Meteoroid stream modelling have gained high precision over the years. Here we compute the structure of the cloud of meteoroids released by comet, showing its dependence on heliocentric ejection distances, 3-dimensional ejection velocities, and particle sizes. Our calculations using numerical integrator MERCURY, [7], incorporating radiation pressure, [8], show that ejection of particles at large heliocentric distances could lead to evolution of a dense meteoroid cloud which intersects Mars a few hours after the comet-Mars close encounter. This detection of a meteor shower on Mars is an indirect confirmation of cometary activity at large distances which has rarely been observed directly by telescopes so far.
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