Empiryczne dowody wielkiego bombardowania (LHB) na Księżycu na podstawie danych zaczerpniętych z Geologicznego atlasu Księżyca

Abstract

Lunar cratering chronology is a basis for chronology of meteorite impacts on Mars, Earth and on the other terrestrial planets. Moon is a calibration plate for cratering record for all inner solar system. There are two methods of preparing lunar flux curve: theoretical size-frequency distribution (SFD) proposed by Neukum et al. (2001) and empirical, based on the samples collected by the space probes Apollo and Luna. In this paper I checked empirically SFD method based on two maps: Geologic Map of the North Side of the Moon (1978) and Geologic Map of the South Side of the Moon (1979) collected in the Geologic Atlas of the Moon. There was count all craters dated on the each of the lunar stratigraphic units. Boundaries of the lunar geologic units are related to impact structures and lava flows. The most problematic is the age of these forms. Most of the known ages of the lunar basins and craters which are the limits of the stratigraphic units (Nectaris, Imbrium and Orientale basins and Copernicus crater – Table 1) were compared in this paper. If the number of craters in the lunar geological period is constant, duration of the geological units affects the diagram of the impact flux (Fig. 3–8). The period with the most intensive frequency of meteorite collisions is called Large Heavy Bombardment (LHB), but, as we see on figures 3–8, it changes depending on the used data. The length and boundaries of LHB period is a clue to understanding of early evolution of terrestrial planets and inner solar system.