Steepness of Slopes at the Luna-Glob Landing Sites: Estimating by the Shaded Area Percentage in the LROC NAC Images

Geological and Geomorphological Characteristics of High-Priority Landing Sites for the Luna-Glob Mission

“…In comparing the results of estimating the inclinations obtained by the NAC and LOLA images for ellipses 1, 4, 6 and B-1, 2, we recorded a noticeable increase in the inclinations greater than 10° during the calculation by the shadow method (Krasilnikov et al, 2018). This is an expected result related to the fact that in using the 0.5-1 m/px images, the shadow method leads to estimating the distribution of inclinations at the base of a few meters, and in the map with a spatial resolution of 60 m/px, these inclinations at the small base are smoothed and the probability of a hazardous slope is underestimated (Table 1).…”

“…The percentage ratio of the different categories of the surface inclinations (<7°, 7°-10°, 10°-15°, 15°-20° and >20°) (Krasilnikov et al, 2018) was calculated according to the LOLA data with the resolution of 60 m/px. The largest concentration of critical inclinations (>10°) is observed in ellipses 7, 10, and 11, while the plain topography, in ellipses 2, 3, and 5.…”

“…To determine the inclinations at the base of a lander footpad span of ~3.5 m, additional studies are required based on determining the share of the shaded surface area in the NAC images with respect to the solar elevation (Abdrakhimov et al, 2015). This method was used for determining the inclinations at the base of the lander module in the primary (1, 4, and 6) and secondary (B-1, -2) landing ellipses in (Krasilnikov et al, 2018). Comparing the results obtained to the previous research using the LOLA database (Djachkova et al, 2017), we can see the difference in the inclinations <7°i n several percent, which is likely related to the different methods of data processing.…”

“…Eleven landing ellipses were proposed and preliminarily analyzed for conformity to engineering constraints in (Djachkova et al, 2017). The ellipses were ranged from the most favorable to the least favorable landing sites in (Djachkova et al, 2017;Krasilnikov et al, 2018). On the totality of technical parameters, ellipse 1 was selected as the primary landing ellipse and ellipses 4 and 6 were secondary ones (Djachkova et al, 2017).…”

“…Two ellipses in Boguslawsky crater, which were previously considered as primary, Boguslawsky-1 (73.9° S; 43.9° E, hereinafter B1) and Boguslawsky-2 (72.9° S; 41.3° E, B2) (Fig. 1), were analyzed in (Ivanov et al, 2015;Krasilnikov et al, 2018). The geology of three primary landing ellipses (1, 4, and 6) was described in (Ivanov et al, 2018).…”