Total Mass Budget of the Zodiacal Dust Cloud from Optical Depth and Particle Size Distribution

This paper examines Total mass of the cloud inferred from its measured optical depth and an area-weighted grain size. Using only published input values and transparent formulae, the calculation obtains the following headline results: vertical_optical_depth_1AU = 1e-07; surface_mass_density_kg_m2_1AU = 1e-08; area_weighted_radius_um = 30; total_cloud_mass_kg = 4.07794e+15; total_cloud_mass_in_1e14kg = 40.78; mass_in_10_to_100um_fraction_estimate = 0.62. The integration gives a total mass of about four times ten to the fifteenth kilograms, comparable to a single modest asteroid, despite the cloud filling the inner Solar System. The method, inputs and limitations are stated in full so that any reader can reproduce or rescale every number from the deposited calculation script. Agreement and disagreement with independent published estimates are reported at their actual size, and the conclusions are limited to what the budget arithmetic supports.