Martian Dust Belts: Waiting for Discovery

Mukai (1992), Krymskii et al. (1992), Tátrallyay et al. (1992), Juhász et al. (1993), Kholshevnikov et al. (1993), In this paper, we present modeling results of the presumed dust belts of Mars. We combine recently obtained theoretical Ishimoto and Mukai (1994), Krivov (1994), Krivov and results in dynamics of circumplanetary dust grains with up-toTitov (1994), Sasaki (1994), Juhász and Horányi (1995), date impact models and use a new numerical code to construct a Baumgärtel et al. (1996), Błȩcka and Jurewicz (1996), Hamthree-dimensional, time-dependent, and size-dependent distriilton (1996), Ishimoto (1996), Krivov and Krivova (1996), bution of dust material. Our modeling is performed in two Krivov et al. (1996a,b), Sasaki (1996a,b), Orofino et al. consecutive stages. First, for each grain size, we construct a (1997), Ishimoto et al. (1997), among others (see Hamilton relative spatial density distribution (i.e., a density distribution 1996 for a detailed summary of previous results). These normalized to an arbitrary factor), which depends almost enefforts have resulted in a vastly revised view of the martian tirely on dust dynamics. We arrive at an extended set of data dust rings; in particular, the orbital dynamics of dust tables which quantitatively describe the asymmetric and seasonaround Mars is now well understood. Our aim in this work dependent structure formed by different-sized grains. This step is to combine accurate orbital dynamics (Juhász and is done quite accurately using sophisticated dynamical models. Next, we model the dust production and loss rates in two Horányi 1995, Hamilton 1996, Ishimoto 1996, Krivov et al. conceivable formation scenarios to estimate absolute spatial 1996a,b, Hamilton and Krivov 1996) with good impact dust densities. These results are uncertain by one or two orders ejecta models (Frisch 1992, Koschny and Grün 1996a,b) of magnitude because the hypervelocity impact process is poorly and a simulation technique (Krivov 1994) to estimate the characterized. We use the absolute spatial densities to estimate spatial dust density in the martian tori quantitatively. In the normal and edge-on optical depths of the Phobos and this paper, we synthesize these recent results and obtain Deimos tori and obtain values from 10 to 10. Spacecraft the first predictions for optical depths and number densities data are required to substantially reduce these uncertainties. of dust in the martian rings that are based on accurate  1997 Academic Press orbital dynamics. Estimating the spatial dust density within the rings is not an easy task since the martian rings are predicted to