In a new era of lunar exploration, pyroclastic deposits have been identified as valuable targets for resource utilization and scientific inquiry. Little is understood about the geomechanical properties and the trafficability of the surface material in these areas, which is essential for successful mission planning and execution. Past incidents with rovers highlight the importance of reliable information about surface properties for future, particularly robotic, lunar mission concepts. Characteristics of 149 boulder tracks are measured in Lunar Reconnaissance Orbiter Narrow Angle Camera images and used to derive the bearing capacity of pyroclastic deposits and, for comparison, mare and highland regions from the surface down to ~5‐m depth, as a measure of trafficability. Results are compared and complemented with bearing capacity values calculated from physical property data collected in situ during Apollo, Surveyor, and Lunokhod missions. Qualitative observations of tracks show no region‐dependent differences, further suggesting similar geomechanical properties in the regions. Generally, bearing capacity increases with depth and decreases with higher slope gradients, independent of the type of region. At depths of 0.19 to 5 m, pyroclastic materials have bearing capacities equal or higher than those of mare and highland material and, thus, may be equally trafficable at surface level. Calculated bearing capacities based on orbital observations are consistent with values derived using in situ data. Bearing capacity values are used to estimate wheel sinkage of rover concepts in pyroclastic deposits. This study's findings can be used in the context of traverse planning, rover design, and in situ extraction of lunar resources.

Permanently shadowed regions (PSRs) are abundant at the lunar poles. They experience no direct sunlight and reach temperatures as low as 30 K. PSRs are of interest as evidence suggests that some may contain water ice (H2O/OH‐), which could provide a record of the evolution of volatiles in the inner solar system. This water ice is also a critical resource for life‐support systems and rocket propellant. A better understanding of mechanical properties of PSR regolith, such as its bearing capacity, will help optimize the design of future exploration rovers and landers. Thirteen boulder tracks were identified on the edge of, or inside, south polar lunar PSR enhanced imagery and used to estimate the strength of the PSR regolith at latitudes of 70° to 76° in sites with maximum annual temperatures of 65 to 210 K. PSR boulder track features are similar to those observed in highland, mare, and pyroclastic regions of the Moon, implying similar properties of the regolith. Measured features were used to estimate bearing capacity for PSR regolith at depths of ~0.28 to 4.68 m. Estimated bearing capacity values suggest that these PSRs may be somewhat stronger than highland and mare regions at depths of 0.28 to 1.00 m. Bearing capacity in these PSRs is statistically the same as those in other regions of the Moon at depths of 1.00 to 2.00 m. The results of this study can be used to infer bearing capacity as one measure for the trafficability of lower‐latitude PSRs of the type measured here.

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Suicide is the leading cause of death among young men aged 15–29 in Greenland, but few epidemiological studies have described this problem. We aimed to summarise descriptive epidemiological studies of suicide in young men in Greenland compared with other demographic groups in Denmark and Greenland to inform future suicide prevention strategy. We searched PubMed, PsycINFO, and Embase using an agreed search strategy to identify English-language papers describing suicide epidemiology in Greenlandic men aged 15–29. We followed PRISMA guidelines in screening and appraising eligible publications. Eight articles fulfilled inclusion criteria of 64 meeting search criteria. Findings covering 1970–2011 supported a dramatic rise in suicide rates in Greenlandic men aged 15–24 from 1976, who remained the highest-ranking demographic group over 1976–2011 compared with men and women of all age groups in Denmark and Greenland. Highest rates recorded were almost 600 per 100,000 per year in men aged approximately 20–23 over 1977–1986. No studies described suicide epidemiology after 2011, and no studies described risk factors for suicide in young men. Given the very high suicide rates recorded for young men over 1976–2011, such studies will be essential for informing the development and evaluation of appropriate preventive interventions.