The meteoritic environment of the Moon

Abstract

Diverse evidence concerning the probable particulate influx on the Moon is assembled along with estimates of the rather large uncertainties. The masses under consideration range from 10 –14 to 10 +18 g, the total estimated influx amounting to the order of 4 × 10 –16 g cm –2 s –1 . The occurrence of large lunar craters assumed to have accumulated over 4 x 10 9 y appears consistent with the expected production rate by Apollo-type asteroids. Cometary nuclei may or may not have contributed significantly. There is possibly a dearth of smaller craters of diameter less than 50 m as compared to the probable production by meteoritic influx. The overturn of lunar material by cratering impacts may have largely blanketed craters with diameters smaller than 3 to 30 m.