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Aiming at the problem that it is difficult to collect the subsurface lunar water ice samples quickly due to the cementation-hardening of ice and soil at extremely low temperature in the permanent shadow regions, a novel lunar water ice sampling system is proposed, which uses kinetic energy penetration to efficiently expose the subsurface lunar water ice and uses manipulator to accurately collect and transfer the lunar soil samples. Based on the analysis of the working strategy of the sampling system, an engineering prototype of penetrating modular was designed and developed, and its penetration efficiency was tested based on the principle that the mechanical characteristics are equivalent. The test results show that the penetrating modular can penetrate into the target whose uniaxial compressive strength(UCS) is about 30Mpa (equivalent to the UCS of the simulated lunar water ice) with low power consumption and high efficiency, the penetration depth can reach 234mm, and the penetration time is less than 1s.

期刊论文 2023-01-01 DOI: 10.1109/ACCESS.2023.3247963 ISSN: 2169-3536

The Moon is generally depleted in volatile elements and this depletion extends to the surface where the most abundant mineral, anorthite, features <6 ppm H2O. Presumably the other nominally anhydrous minerals that dominate the mineral composition of the global surface-olivine and pyroxene-are similarly depleted in water and other volatiles. Thus the Moon is tabula rasa for the study of volatiles introduced in the wake of its origin. Since the formation of the last major basin (Orientale), volatiles from the solar wind, from impactors of all sizes, and from volatiles expelled from the interior during volcanic eruptions have all interacted with the lunar surface, leaving a volatile record that can be used to understand the processes that enable processing, transport, sequestration, and loss of volatiles from the lunar system. Recent discoveries have shown the lunar system to be complex, featuring emerging recognition of chemistry unanticipated from the Apollo era, confounding issues regarding transport of volatiles to the lunar poles, the role of the lunar regolith as a sink for volatiles, and the potential for active volatile dynamics in the polar cold traps. While much has been learned since the overturn of the Moon is dry paradigm by innovative sample and spacecraft measurements, the data point to a more complex lunar volatile environment than is currently perceived.

期刊论文 2022-09-01 DOI: 10.1016/j.chemer.2021.125858 ISSN: 0009-2819

The northern floor and wall of Amundsen crater, near the lunar south pole, is a permanently shaded region (PSR). Previous study of this area using data from the Lunar Orbiter Laser Altimeter (LOLA), Diviner and LAMP instruments aboard Lunar Reconnaissance Orbiter (LRO) shows a spatial correlation between brighter 1064 nm albedo, annual maximum surface temperatures low enough to enable persistence of surface water ice (< 110 K), and anomalous ultraviolet radiation. We present results using data from Diviner that quantify the differential emissivities observed in the far-IR (near the Planck peak for PSR-relevant temperatures) between the PSR and a nearby non-PSR target in Amundsen Crater. We find features in far-IR emissivity (50-400 mu m) could be attributed to either, or a combination, of two effects (i) differential regolith emissive behavior between permanently-shadowed temperature regimes and those of normally illuminated polar terrain, perhaps related to presence of water frost (as indicated in other studies), or (ii) high degrees of anisothermality within observation fields of view caused by doubly-shaded areas within the PSR target that are colder than observed brightness temperatures. The implications in both cases are compelling: The far-IR emissivity curve of lunar cold traps may provide a metric for the abundance of micro cold traps that are ultra-cool, i.e. shadowed also from secondary and higher order radiation (absorption and re-radiation or scattering by surrounding terrain), or for emissive properties consistent with the presence of surface water ice.

期刊论文 2019-11-01 DOI: 10.1016/j.icarus.2019.06.002 ISSN: 0019-1035

Searching for water-ice in the lunar media has been a key issue in the moon explorations. Missions of mini-SAR and mini-RF SAR made compact-pol (polarization) measurements on lunar polar permanent shadowed region (PSR). High circular polarization ratio (CPR) data and a two-layer model were applied to studying if water ice in PSR could be retrieved. However, it has been studied that high CPR is not simply due to the presence of water ice, and the Campbell model is a degenerated half-space model, which confused final inversion. In this letter, using the mini-RF data on the PSR of Hermite-A crater on the north pole, a two-layer model with the Kirchhoff and small perturbation approximations is presented. It takes account of the surface-layering topography, which makes changes of local incidence and polarimetric base rotation. Our results do not support Calla's conclusions based on the half-space model, suggesting that the inversion of mini-RF is not so straightforward in proving water-ice existence in the PSR media. It points out that the double- and high-order scattering of random volumetric scatters on the lunar surface might play a role, and high-resolution measurements and more elaborate modeling are needed for further studies.

期刊论文 2018-10-01 DOI: 10.1109/LGRS.2018.2852139 ISSN: 1545-598X
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