Aitken basin

Pieters C. M., Head J. W., Ill, Gaddis L., Jolliff L., and Duke M. (2001) Rock types of South Pole-Aitken basin and extent of basaltic volcanism. J. Geophys. Res. 106, 28001-28022. 

The Hadean impact record is best calibrated to the large lunar hasins (Zahnle Sleep 1996 Anbar et al. 2001). To order of magnitude, the mass of the typical basin-forming impactor was c. 10 g although the archtypes (e.g. Orien-tale) were larger, c. 10 g and the largest that remains clearly visible (S. Pole-Aitken), perhaps... 

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