ИСТИНА

The southern circumpolar region of the Moon (SCR) is a geologically complex area [1] whose topography waslargely formed by four major impact events[2–3]: the South Pole-Aitken (SPA), Bailly, Amundsen-Ganswindt, and Schrödinger basins. The close areal clustering of the four basins suggests that their ejecta came from similar crustal (and possibly mantle) domains of the Moon [4]. The Artemis region [5] is in a zone interpreted to be on the rim of the SPA basin where the ejecta could be contiguous and thick. Their estimated model thickness is ~5.4 km. Most of successive impacts [1] caused excavation and re-distribution of the SPA ejecta materials, which therefore could potentially be found throughout the SCR and in all Artemis sites as well. Diameters of the post-SPA basins, Bailly, Amundsen-Ganswindt, and Schrödinger vary from ~300 to ~350 km. This means that the excavation depth of their impacts exceeded the model thickness of the SPA ejecta, and ejecta deposits of these basins likely contain a significant proportion of materials characterizing the earliest (pre-SPA) stages of lunar evolution. Thus, ejecta of these basins has very high scientific potential. The region of the Artemis landing sites is near the southern portion of the Amundsen-Ganswindt basin. This basin is thus likely to represent the major contributor of materials that have been deposited at the landing sites. The Amundsen-Ganswindt basin (AGB, ~350 km diameter) is within the Mg-pyroxene zone of the SPA, away from the central compositional anomaly of the basin [6]. The AGB impact likely excavated materials that are not contaminated by SPA impact melt.