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Microwave emission is influenced by regolith thermophysical properties that can reveal the geological evolution of the Moon. Lunar near-surface microwave emission has been systematically investigated by the microwave radiometer (MRM) onboard Chinese Chang'E-2 (CE-2) lunar satellite. However, recent work showed that global calibration issues were causing discrepancies between CE-2 observations and theoretical simulations at 3.0- and 7.8-GHz channels, which influences data interpretations and applications. In this study, we use a new method to improve thermal models by employing the bolometric brightness temperature and thermophysical property of subsurface structure derived from high quality and repeated coverage Diviner data. The derived subsurface temperatures make it possible for us to improve the accuracy of microwave brightness temperature (TB) simulation within 70°N/S latitudes. We evaluate the MRM data quantitatively by comparing the global TB between modeled values and CE-2 observations (i.e., offset values) at different local times (LTs) and latitudes. The results show that offset values of the two channels vary significantly with LT, especially near 06:00 and 18:00. However, the 7.8-GHz channel presents greater (~12k in average) calibration uncertainties than the 3.0-GHz channel. In addition, the offset of both the two channels becomes complex at high latitudes but presents an obvious north-south asymmetry. Finally, we modify the MRM data according to different offsets at different LTs and latitudes. The modified global TB maps provide us a new view to characterize the lunar near-surface thermal environment, especially for low-TB spots that are related to the elevated rock abundance and crater degradation.

The composition of Bolides acts somewhat like a series of snapshots or a diary of my life between March 2020 and December 2021, and for me evokes geographical and temporal cues that are very specific for that particular point in time. The source material includes underwater recordings of kelp forests, captured by homemade hydrophones, the ululations of grey seal pups, and an improvised percussion performance on plate steel. The compositional methodology was guided by an aural discourse, and the structural decisions throughout the process were informed by the materials as they presented themselves, there were no abstract processes involved. Sound objects were chosen for their gestural and sonic properties, and then further processed using a mixture of real-time interaction facilitated by a Leap motion sensor and a multitouch-surface MIDI controller. Both of these devices were mapped to parameters of various DSP devices, some of which were created using Csound, some of which are native to Ableton Live 11. A series of performances were recorded using this configuration and the results of these gesturally-driven performances were further developed into the library of sound objects that make up this piece.

Deciphering paleoclimate on Mars has been a driving goal of Martian science for decades. Most research has addressed this issue by studying Mars' large polar layered deposits (PLDs) as a paleoclimate proxy, but the certainty to which we know the link between climate and orbit is debated. Here, we instead consider the record of other, smaller ice deposits located within craters separated from the PLDs using images from NASA's High Resolution Imaging Science Experiment camera and signal processing techniques. We show that the climate record in Burroughs Crater (72.3°S, 116.6°E) contains robust evidence of orbital forcing, with periodicities that have wavelengths of 15.6 and 6.5 m. The ratio of these dominant wavelengths is 2.4, the same as the ratio between the periods of Mars' obliquity changes and orbital precession. This result suggests orbital control of recent Mars climate, and would imply an average ice accumulation rate of 0.13 mm/yr over 4.5 Myr in this region.

Topographic depressions within permanently shadowed regions (PSRs) on low-obliquity planetary bodies can be shielded not only from direct illumination, but also from scattered sunlight and thermal emission from nearby sunlit surfaces. We apply an illumination model to high-resolution topography data to produce the first map of double shadows at the lunar poles. The total doubly shadowed area resolved at the 30 m scale is 1.47 km2 in the northern hemisphere and 5.37 km2 in the southern hemisphere, predominantly contained within small craters on the floors of large permanently shadowed craters. In total, ∼0.04% of PSR area is permanently double shadowed, but the largest double shadows are nearly 600 m across, potentially large enough to be resolved in remote sensing temperature measurements. In the absence of secondary heating sources, double shadows are predicted to be significantly colder than singly shadowed areas and could sequester highly volatile compounds like carbon dioxide. Future in situ investigation of the regions identified in this work can elucidate the origin and distribution of the Moon’s most volatile deposits.

The surfaces of airless bodies like the Moon are bombarded by a steady stream of small impactors that lead to erosion of the topography over time. However, the rate of degradation from small impacts, a key parameter in interpreting the ages of present-day lunar surface features, is not well constrained. Here we demonstrate, using a numerical mass transport model, that impact erosion is a nonlinear diffusion process, in contrast to past studies of crater degradation that have assumed that the downslope mass flux of ejecta is linearly proportional to hillslope gradient. Nonlinearity is a consequence of the asymmetric shape of ejecta blankets on sloped surfaces, and as a result, the degradation rate on steep slopes is over 40% greater than on nearly flat surfaces. Using measurements of the morphology and formation rate of small primary and secondary craters, the kilometer-scale lunar landscape diffusivity is computed and compared to the value inferred from topographic profiles of degraded craters. We show that the abundance of decameter-scale craters forming on the Moon over the past decade is consistent with small impacts dominating the erosion of the lunar landscape, but only if the primary size−frequency distribution remains steep down to the submillimeter scale.