Depth to Diameter Analysis on Small Simple Craters at the Lunar South Pole—Possible Implications for Ice Harboring

Abstract

In this paper, we present a study comparing the depth to diameter (d/D) ratio of small simple craters (200–1000 m) of an area between -88.5 to -90 latitude at the lunar south pole containing Permanent Shadowed Regions (PSRs) versus craters without PSRs. As PSRs can reach temperatures of 110 K and are capable of harboring volatiles, especially water ice, we analyzed the relationship of depth versus diameter ratios and its possible implications for harboring water ice. Variations in the d/D ratios can also be caused by other processes such as degradation, isostatic adjustment, or differences in surface properties. The conducted d/D ratio analysis suggests that a differentiation between craters containing PSRs versus craters without PSRs occurs. Thus, a possible direct relation between d/D ratio, PSRs, and water ice harboring might exist. Our results suggest that differences in the target’s surface properties may explain the obtained results. The resulting d/D ratios of craters with PSRs can help to select target areas for future In-Situ Resource Utilization (ISRU) missions.

ShadowCam Instrument and Investigation Overview

“…Various observations have accurately delimited the locations of PSRs (Shoemaker et al 1994;Bussey et al 1999Bussey et al , 2003Bussey et al , 2010Noda et al 2008;BusseyMazarico et al 2011;Zuber et al 2012;Gläser et al 2014;Hayne et al 2021;Schorghofer et al 2021) and thermal observations indicate where various volatiles are thermally stable within PSRs (Zhang & Paige 2009;Paige et al 2010;Gläser et al 2021). These observations of where water ice could be stable do not perfectly correlate with where the sum of currently available measurements suggest ice is located (e.g., from neutron absorption (Feldman et al 2000(Feldman et al , 2001Mitrofanov et al 2010;Miller et al 2014), or reflectance variations (e.g., Gladstone et al 2012;Lucey et al 2014;Li et al 2018, see reviews in Brown et al 2022;Lucey et al 2022), or topographic anomalies (Figuera et al 2022).…”

Lunar Cold Microtraps as Future Source of Raw Materials—Business and Technological Perspective

“…The ranking of cold traps in terms of the abundance of volatile substances can be found in the publication [41]. In turn, publication [42] presents the relationship between the crater depth and diameter ratio (d/D). The authors analyzed the d/D ratio for 753 craters ranging from 200 to 1000 miles in diameter and with an inclination of less than 25 • located at the Moon's south pole and grouped the craters into two groups: craters containing perennially shadowed regions (PSR) and those without PSR.…”

Cartography of the Solar System: Remote Sensing beyond Earth

“…Due to their rich variety of erosional states and complex arrangements, manual selection methods of impact craters have been the most reliable thus far. In [11], the authors present an investigation on the depth/diameter ratio of lunar impact craters at the South pole and implications for harboring water ice.…”

“…Mapping and spectral analysis [1][2][3][4][5][6][7]; • Data processing and data products [8][9][10]; • Impact crater and feature detection [11,12]; • Pose estimation [13,14]; • Research data management and valuation [15,16].…”