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The Lunar CRater Observations and Sensing Satellite (LCROSS) impacted a Centaur rocket stage into a permanently shadowed region (PSR) in Cabeus crater, excavating water ice and other volatiles. We used the Miniature Radio Frequency (Mini‐RF) instrument on the Lunar Reconnaissance Orbiter and the ShadowCam instrument on the Korean Pathfinder Lunar Orbiter to detect the probable 22‐m diameter crater that resulted from the LCROSS impact. The crater formed superposed upon a dense small crater population along a crater ray from a larger pre‐existing crater. From its geologic context, the ice and regolith excavated by LCROSS were likely modified within the last 0.1–0.5 Gyr. An upper limit for the excavated volatiles is ~0.9 Gyr, as the location was not a PSR prior to that time. A young age for the LCROSS‐detected volatiles supports the idea that they were mostly emplaced by an exogenic mechanism, such as from comets or the solar wind. Plain Language Summary: The LCROSS experiment formed an impact crater in an area of permanent shadow on the Moon, striking the surface at 2.5 km/s with a 2,300 kg spent rocket body on 9 October 2009. The impact ejecta from this cratering event included detectable amounts of water and other volatiles, which is perhaps the most direct evidence for significant water deposits on the Moon. However, since the impact location is in permanent shadow (no direct solar illumination), it proved hard to observe definitively the crater that LCROSS formed. Here, we use data from Mini‐RF, which illuminated the surface with S‐band radar, combined with ShadowCam, which acquires images within permanent shadows, to find the probable LCROSS impact crater. The impact crater is 22‐m in diameter, a bit smaller than was inferred indirectly after LCROSS. We also present new evidence that the volatiles in the ejecta likely got there in the last 20% of lunar history, which is important for understanding their origin and evolution. Key Points: We used Mini‐RF and ShadowCam to locate the 22‐m crater formed by LCROSS within a permanently shadowed region near the Moon's south poleGiven the crater's size, the regolith that was excavated, including volatiles, likely came from approximately the upper 2 mThe geologic context of the LCROSS crater suggests that the volatiles it excavated were relatively young, from the Copernican epoch [ABSTRACT FROM AUTHOR]

The Moon is a highly valued destination for human space exploration because it is close and it contains a wide array of lunar and Solar System science targets, which include resources that could be used to sustain humans on the lunar surface. These resources have the potential to enable sustainable human space exploration, develop a vibrant cislunar economy, and directly benefit society here on Earth. However, recent rhetoric about the importance and value of these resources has used the term as if we know they are reserves. An immediate and vital next step has not yet been realized to define the reserve potential of such resources, and that is designing and implementing a coordinated international lunar resource evaluation (prospecting) campaign. This paper outlines the issues that need to be addressed by such a campaign, including why it needs to be international in nature and how the coordination can be started and evolved, as well as exploring the benefits that would come from prospecting on the Moon. • A distinction between lunar resources and lunar reserves is defined. • Roadblocks in the in-situ resource value chain are highlighted. • Reserve potential of lunar resources requires a coordinated prospecting campaign. • The prospecting campaign must be international due to the scale of the task. • Coordination can start at the grassroots level with current and scheduled missions. [ABSTRACT FROM AUTHOR]

Abstract: The mostly carbon dioxide (CO2) atmosphere of Mars condenses and sublimes in the polar regions, giving rise to the familiar waxing and waning of its polar caps. The signature of this seasonal CO2 cycle has been detected in surface pressure measurements from the Viking and Pathfinder landers. The amount of CO2 that condenses during fall and winter is controlled by the net polar energy loss, which is dominated by emitted infrared radiation from the cap itself. However, models of the CO2 cycle match the surface pressure data only if the emitted radiation is artificially suppressed suggesting that they are missing a heat source. Here we show that the missing heat source is the conducted energy coming from soil that contains water ice very close to the surface. The presence of ice significantly increases the thermal conductivity of the ground such that more of the solar energy absorbed at the surface during summer is conducted downward into the ground where it is stored and released back to the surface during fall and winter thereby retarding the CO2 condensation rate. The reduction in the condensation rate is very sensitive to the depth of the soil/ice interface, which our models suggest is about 8cm in the Northern Hemisphere and 11cm in the Southern Hemisphere. This is consistent with the detection of significant amounts of polar ground ice by the Mars Odyssey Gamma Ray Spectrometer and provides an independent means for assessing how close to the surface the ice must be. Our results also provide an accurate determination of the global annual mean size of the atmosphere and cap CO2 reservoirs, which are, respectively, 6.1 and 0.9hPa. They also indicate that general circulation models will need to account for the effect of ground ice in their simulations of the seasonal CO2 cycle. [Copyright &y& Elsevier]

Results are reported from a new lunar base study with a concise architectural program: build and operate a human-tended base that produces enough oxygen and hydrogen from lunar polar ice In-Situ Resource Utilization (ISRU) for four flights per year of a reusable lander shuttling between the Lunar Gateway and the base. The study examines for the modern era issues first developed and reconciled by the Robotic Lunar Surface Operations (RLSO) study published in 1990 and resurrected at the 69th IAC in Bremen. The new study updates key assumptions for 1) resources - lunar polar ice instead of ilmenite; 2) solar power - polar lighting conditions instead of the 28-day equatorial lunation cycle; 3) transportation - use of multiple flight systems now in development and planning; 4) base site planning - a range of options near, straddling, and inside permanently shadowed regions; 5) ISRU scenarios - for harvesting ice and for constructing radiation shielding from regolith. As did the original study, RLSO2 combines US experts in mission design, space architecture, robotic surface operations, autonomy, ISRU, operations analysis, and human space mission and lunar surface experience. Unlike the original study, the new study uses contemporary tools: CAD engineering of purpose-design base elements, and integrated performance captured in a numerical operations model. This allows rapid iteration to converge system sizing, and builds a legacy analysis tool that can assess the performance benefits and impacts of any proposed system element in the context of the overall base. The paper presents an overview of the ground rules, assumptions, methodology, operations model, element designs, base site plan, and quantitative findings. These findings include the performance of various regolith and ice resource utilization schemes as a function of base location and lunar surface parameters. The paper closes with short lists of the highest priority experiments and demonstrations needed on the lunar surface to retire key planning unknowns. • It is critical to design all base elements concurrently so that they are integrated. • The base architecture must be built around quantified operations analysis. • For a large portion of time, the base must be constructed and tended to robotically. • The scale of the ISRU operations will be too large for constant human involvement. [ABSTRACT FROM AUTHOR]

Lunar Crater Observation and Sensing Satellite (LCROSS) impacted the Cabeus crater near the lunar South Pole on 9 October 2009 and generated an impact plume. The hydroxyl (OH) band strength observations obtained from the LCROSS mission are explained with the help of numerical modeling of the impact plume. We provide different models of OH production in the plume and conduct a parametric study to constrain the independent parameters of these models. In particular, detailed lofted grain heating, sublimation and photodissociation models are implemented along with models for H2O and OH production from the residual impact crater. Results show that the likely sources of observed OH are from a small amount of direct/abrasional OH desorption from regolith grains (~28 g) in the crater and from sublimation of water vapor (O (800 kg)) from lofted regolith-imbued ice grains followed by photodissociation. [ABSTRACT FROM AUTHOR]

Mastcam-Z is a multispectral, stereoscopic imaging investigation on the Mars 2020 mission's Perseverance rover. Mastcam-Z consists of a pair of focusable, 4:1 zoomable cameras that provide broadband red/green/blue and narrowband 400-1000 nm color imaging with fields of view from 25.6° × 19.2° (26 mm focal length at 283 μrad/pixel) to 6.2° × 4.6° (110 mm focal length at 67.4 μrad/pixel). The cameras can resolve (≥ 5 pixels) ∼0.7 mm features at 2 m and ∼3.3 cm features at 100 m distance. Mastcam-Z shares significant heritage with the Mastcam instruments on the Mars Science Laboratory Curiosity rover. Each Mastcam-Z camera consists of zoom, focus, and filter wheel mechanisms and a 1648 × 1214 pixel charge-coupled device detector and electronics. The two Mastcam-Z cameras are mounted with a 24.4 cm stereo baseline and 2.3° total toe-in on a camera plate ∼2 m above the surface on the rover's Remote Sensing Mast, which provides azimuth and elevation actuation. A separate digital electronics assembly inside the rover provides power, data processing and storage, and the interface to the rover computer. Primary and secondary Mastcam-Z calibration targets mounted on the rover top deck enable tactical reflectance calibration. Mastcam-Z multispectral, stereo, and panoramic images will be used to provide detailed morphology, topography, and geologic context along the rover's traverse; constrain mineralogic, photometric, and physical properties of surface materials; monitor and characterize atmospheric and astronomical phenomena; and document the rover's sample extraction and caching locations. Mastcam-Z images will also provide key engineering information to support sample selection and other rover driving and tool/instrument operations decisions., Competing Interests: Conflicts of interest/Competing interestsThe authors declare that they have no conflict of interest., (© The Author(s) 2020.)