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Conceptual cross section of a 30 m diameter non–rocky ejecta crater (left) and a 60 m diameter rocky ejecta crater (right). Ejecta is sourced from 0.084 times the crater diameter (marked by the asterisk, *), so the non‐REC indicates the fragmented regolith is at least 2.5 m thick. The REC indicates the regolith must be thinner than its ejecta source depth of 5 m. The actual thickness of the regolith must be between these two (i.e., >2.5 and <5 m).
