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The Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) images and their derived products make up one of the highest-resolution and most spatially accurate data sets available for the Moon, making them a crucial resource for planners of landed lunar missions. However, it is essential to understand the best uses for each data type and the limits on the accuracy and resolution of the data sets available. With this understanding, users can better interpret and communicate their results. In this paper, we describe what assumptions may be made about the accuracy of LROC NAC images and the various derived products created by the LROC team. NAC digital terrain models and their corresponding orthophotos have the best accuracy of all NAC products, usually better than 10 m horizontally, and should be used where available. Other controlled NAC products usually have accuracies better than 30 m. For areas without controlled products, we describe how to process NAC images to obtain coordinates with the highest possible accuracy. We also recommend best practices for data users interacting with LROC data through online map servers, such as QuickMap or Lunaserv, and for processing LROC data locally using the US Geological Survey Integrated Software for Imagers and Spectrometers.

Faustini crater (41 km diameter) hosts a large (664 km ^2 ) permanently shadowed region (PSR) with a high potential to harbor water-ice deposits. One of the 13 candidate Artemis III landing areas contains a portion of the crater rim and proximal ejecta. The ShadowCam instrument aboard the Korea Pathfinder Lunar Orbiter provides detailed images of the PSR within Faustini. We characterize the terrain and thermal environment within the Faustini PSR from ShadowCam images, Lunar Reconnaissance Orbiter thermal measurements and laser ranging, and thermal modeling. Our mapping revealed three distinct areas of the floor of Faustini based on elevations, slopes, and surface roughness. These units broadly correlate with temperatures; thus, they may be influenced by variations in volatile sublimation. Crater retention and topographic diffusion rates appear to be asymmetric across the floor, likely due to differences in maximum and average temperatures. Several irregular depressions and a pronounced lobate-rim crater are consistent with subsurface ice. However, differences in the thicknesses of deposited materials on the floor may also explain the asymmetry. Additionally, zones of elevated surface roughness across Faustini appear to result from overprinted crater ray segments, possibly from Tycho and Jackson craters. Mass wasting deposits and pitting on opposite sides of the crater wall may have resulted from the low-angle delivery of material ejected by the Shackleton crater impact event, suggesting that the Artemis III candidate landing region named “Faustini Rim A” will contain material from Shackleton.

We provide the first solar system wide compendium of speleogenic processes and products. An examination of 15 solar system bodies revealed that six cave‐forming processes occur beyond Earth including volcanic (cryo and magmatic), fracturing (tectonic and impact melt), dissolution, sublimation, suffusion, and landslides. Although no caves (i.e., confirmed entrances with associated linear passages) have been confirmed, 3,545 SAPs (subsurface access points) have been identified on 11 planetary bodies and the potential for speleogenic processes (and thus SAPs) was observed on an additional four planetary bodies. The bulk of our knowledge on extraterrestrial SAPs is based on global databases for the Moon and Mars, which are bodies for which high‐resolution imagery and other data are available. To further characterize most of the features beyond the Moon and Mars, acquisition (preferably global coverage) and subsequent analysis of high‐resolution imagery will be required. The next few decades hold considerable promise for further identifying and characterizing caves across the solar system. Plain Language Summary: Until the last two decades, the potential for caves beyond Earth was principally theoretical. Today, databases of subsurface access points (SAPs) exist for the Moon and Mars. Across the solar system, 3,545 SAPs have been identified on 11 planetary bodies with speleogenic processes identified on another four bodies. Six cave‐forming processes beyond Earth have been identified; these include volcanic (cryo and magmatic), fracturing (tectonic and impact melt), dissolution, sublimation, suffusion, and landslides. As more orbiter and fly by platforms with high‐resolution instrumentation probe the solar system, our knowledge regarding caves beyond Earth will become more robust—culminating with the robotic and perhaps human exploration of caves on the Moon and Mars. Key Points: Six speleogenic processes have been identified across the solar systemTwo speleogenic processes were documented—which are driven by different fluids than on Earth—cryovolcanism and methane‐based dissolutionAt least 3,545 subsurface access points have been identified on 11 planetary bodies with speleogenic processes observed on an additional four bodies [ABSTRACT FROM AUTHOR]

Nearly half a century ago, two papers postulated the likelihood of lunar lava tube caves using mathematical models. Today, armed with an array of orbiting and fly‐by satellites and survey instrumentation, we have now acquired cave data across our solar system—including the identification of potential cave entrances on the Moon, Mars, and at least nine other planetary bodies. These discoveries gave rise to the study of planetary caves. To help advance this field, we leveraged the expertise of an interdisciplinary group to identify a strategy to explore caves beyond Earth. Focusing primarily on astrobiology, the cave environment, geology, robotics, instrumentation, and human exploration, our goal was to produce a framework to guide this subdiscipline through at least the next decade. To do this, we first assembled a list of 198 science and engineering questions. Then, through a series of social surveys, 114 scientists and engineers winnowed down the list to the top 53 highest priority questions. This exercise resulted in identifying emerging and crucial research areas that require robust development to ultimately support a robotic mission to a planetary cave—principally the Moon and/or Mars. With the necessary financial investment and institutional support, the research and technological development required to achieve these necessary advancements over the next decade are attainable. Subsequently, we will be positioned to robotically examine lunar caves and search for evidence of life within Martian caves; in turn, this will set the stage for human exploration and potential habitation of both the lunar and Martian subsurface. Plain Language Summary: We have now acquired cave data across our solar system—including the identification of potential cave entrances on the Moon, Mars, and at least nine other planetary bodies. These discoveries gave rise to the study of planetary caves. To help advance this field, we conducted an expert‐opinion based social survey to identify a strategy to explore caves beyond Earth. We focused primarily on astrobiology, the cave environment, geology, robotics, instrumentation, and human exploration. First, we assembled a list of 198 science and engineering questions. Then, through a series of social surveys, 114 scientists and engineers winnowed down the list to the top 53 highest priority questions. This exercise resulted in identifying emerging and crucial research areas that require robust development to ultimately support a robotic mission to a planetary cave—principally the Moon and/or Mars. With the necessary financial investment and institutional support, the research and technological development required to achieve these necessary advancements over the next decade are attainable. Subsequently, we will be positioned to robotically examine lunar caves and search for evidence of life within Martian caves; in turn, this will set the stage for human exploration and potential habitation of both the lunar and Martian subsurface. Key Points: Robotics and instrument advancements identified as linchpin focal areas for in situ study of planetary cavesResearch and technological development required for lunar and/or Martian cave exploration is achievable in next decade with proper investmentFirst application of systematic and statistically rigorous social survey to identify science and engineering requirements in planetary science [ABSTRACT FROM AUTHOR]

Author(s): Emerson J. Speyerer (corresponding author) [1]; Reinhold Z. Povilaitis [1]; Mark S. Robinson [1]; Peter C. Thomas [2]; Robert V. Wagner [1] Random bombardment by comets, asteroids and associated [...]