Expected features of martian dust belts

Alexander V. Krivov and Natalia A. Krivova

The subject of this study is the dust complex around Mars formed by the dust grains emitted from Phobos and Deimos. Relatively large particles (thought to be the most abundant) are concentrated in toroidal belts along the moons' orbits. We construct an improved model of these tori (or disks) around both satellites. We apply the semi-analytical technique developed in (Krivov, 1994, Astron. Astrophys., 291, 657-663) and use our latest results on dust particles dynamics (Krivov et al., in this volume). The model provides a number density distribution of different-sized grains at different points near Mars. Having the distribution known, we then make rough estimates of the detectability of the dust belts. Our preliminary conclusions are: (i) the direct on-board registration of the Deimos torus is definitely possible; (ii) the optical depth of the Deimos belt and its thermal emission are near the sensitivity limits of to-date instruments, so that the attempts to reveal the complex either by Earth-based visual or infrared photometry would be profitable. For Phobos, detectability of its disk is questionable at present.