LINK<\/strong><\/a><\/p>\n\n\n\n\u201eThe lunar crater record features \u223c50 basins. The radiometric dating of Apollo samples indicates that the Imbrium basin formed relatively late \u2013 from the planet formation perspective \u2013 some \u22433.9Ga. Here we develop a dynamical model for impactors in the inner solar system to provide context for the interpretation of the lunar crater record. The contribution of cometary impactors is found to be insignificant. Asteroids produced most large impacts on the terrestrial worlds in the last \u22433 Gyr. The great majority of early impactors were rocky planetesimals left behind at \u223c0.5\u20131.5 au after the terrestrial planet accretion. The population of terrestrial planetesimals was reduced by disruptive collisions in the first t\u223c20 Myr after the gas disk dispersal. We estimate that there were \u223c4×10\u22275 diameter d>10 km bodies when the Moon formed (total planetesimal mass \u223c0.015MEarth at t\u223c50 Myr). The early bombardment of the Moon was intense. To accommodate \u223c50 known basins, the lunar basins that formed before \u22434.35\u20134.41 Ga must have been erased. The late formation of Imbrium occurs with a \u223c15\u201335% probability in our model. About 20 d>10-km bodies were expected to hit the Earth between 2.5 and 3.5 Ga, which is comparable to the number of known spherule beds in the late Archean. We discuss implications of our model for the lunar\/Martian crater chronologies, Late Veneer, and noble gases in the Earth atmosphere.\u201c<\/p>\n","protected":false},"excerpt":{"rendered":"
David Nesvorn\u00fd, Fernando V. Roig, David Vokrouhlick\u00fd, William F. Bottke, Simone Marchi, Alessandro Morbidelli, Rogerio Deienno Icarus, Available online 29 March 2023, 115545 LINK \u201eThe lunar crater record features \u223c50 basins. The radiometric dating of…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[90,41,115,73],"tags":[1279,2210,2888,2343,642,1284,2530,1858,1009],"_links":{"self":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/33004"}],"collection":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=33004"}],"version-history":[{"count":1,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/33004\/revisions"}],"predecessor-version":[{"id":33005,"href":"https:\/\/karmaka.de\/index.php?rest_route=\/wp\/v2\/posts\/33004\/revisions\/33005"}],"wp:attachment":[{"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=33004"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=33004"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/karmaka.de\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=33004"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}