CLASSIFICATION OF THE UPDATED CATALOG OF RECENT IMPACT SITES ON MARS

Abstract

In recent decades, fresh impacts of meter-scaled cosmic bodies were discovered on Mars. Approximately half of these objects are destroyed in the rarefied atmosphere of Mars and their impacts lead to the formation of crater clusters (crater scattering fields). The expanded impact site catalog includes data on 1438 recent dated impact sites formed between 2007 and 2021. This paper considers a large part of the expanded catalog, for which data on the size and location of craters in clusters are available. Expanded catalog data provided an opportunity to estimate the exponent in the differential and cumulative incremental distribution as 2.7 and 2.2. The obtained estimate of the cumulative distribution exponent is lower than suggested in most studies, but it is close to the estimates obtained from the non-expanded catalog. In order to classify crater clusters, it was proposed to group them into 3 types: the first has a dominant main crater, the second collects 2 largest comparable craters, and the third has 3 or more comparable largest craters, in all cases largest craters may be supplemented (or not) by significantly smaller craters. We are assuming that the identified groups may correspond to different types of impactors and (or) different types of meteoroid destruction in the atmosphere.