Lunar Ejecta Contribution to the Near-Earth Dust Environment

This paper examines Upper bound on dust supplied to near-Earth space by impact ejecta escaping the Moon. Using only published input values and transparent formulae, the calculation obtains the following headline results: lunar_impactor_influx_tonnes_per_day = 30; adopted_ejecta_yield_ratio = 1000; escape_fraction = 2e-05; escaping_ejecta_tonnes_per_day = 0.6; escaping_ejecta_fraction_of_earth_influx_percent = 0.01; bound_note_percent_direct = 0.01; upper_bound_if_all_reached_earth_percent = 1. Even with a generous ejecta yield, material escaping the Moon amounts to at most a percent-level contribution once geometric dilution between the Moon and Earth is included, so lunar ejecta cannot dominate the near-Earth population. 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.