scholarly journals Volcanic history of the Imbrium basin: A close-up view from the lunar rover Yutu

2015 ◽  
Vol 112 (17) ◽  
pp. 5342-5347 ◽  
Author(s):  
Jinhai Zhang ◽  
Wei Yang ◽  
Sen Hu ◽  
Yangting Lin ◽  
Guangyou Fang ◽  
...  
Keyword(s):  
Lunar Regolith ◽  
Landing Site ◽  
Lunar Soil ◽  
Lunar Rover ◽  
Surface Exploration ◽  
Mantle Reservoir ◽  
History Of ◽  
Radar Measurements ◽  
Residual Melt

We report the surface exploration by the lunar rover Yutu that landed on the young lava flow in the northeastern part of the Mare Imbrium, which is the largest basin on the nearside of the Moon and is filled with several basalt units estimated to date from 3.5 to 2.0 Ga. The onboard lunar penetrating radar conducted a 114-m-long profile, which measured a thickness of ∼5 m of the lunar regolith layer and detected three underlying basalt units at depths of 195, 215, and 345 m. The radar measurements suggest underestimation of the global lunar regolith thickness by other methods and reveal a vast volume of the last volcano eruption. The in situ spectral reflectance and elemental analysis of the lunar soil at the landing site suggest that the young basalt could be derived from an ilmenite-rich mantle reservoir and then assimilated by 10–20% of the last residual melt of the lunar magma ocean.

Charged-particle track analysis, thermoluminescence and microcratering studies of lunar samples

1977 ◽  
Vol 285 (1327) ◽  
pp. 309-317 ◽  
Keyword(s):  
Storage Temperature ◽  
Lunar Regolith ◽  
Lunar Soil ◽  
Heavy Ion ◽  
Abundance Ratio ◽  
Temperature Cycle ◽  
The Moon ◽  
Lunar Samples ◽  
History Of ◽  
Track Analysis

Studies of lunar samples (from both Apollo and Luna missions) have been carried out, using the track analysis and thermoluminescence (t.l.) techniques, with a view to shedding light on the radiation and temperature histories of the Moon. In addition, microcraters in lunar glasses have been studied in order to elucidate the cosmic-dust impact history of the lunar regolith. In track studies, the topics discussed include the stabilizing effect of the thermal annealing of fossil tracks due to the lunar temperature cycle; the ‘radiation annealing’ of fresh heavy-ion tracks by large doses of protons (to simulate the effect of lunar radiation-damage on track registration); and correction factors for the anisotropic etching of crystals which are required in reconstructing the exposure history of lunar grains. An abundance ratio of ca. (1.1 + 0.3) x 10-3 has been obtained, by the differential annealing technique, for the nuclei beyond the iron group to those within that group in the cosmic rays incident on the Moon. The natural t.l. of lunar samples has been used to estimate their effective storage temperature and mean depth below the surface. A suite of samples from known depths in an artificial trench at the Apollo 17 site has been used to calculate the effective thermal conductivity and thermal wavelength of overlying lunar soil at various depths. The temperatures in the shadow of some Apollo 17 boulders, and the duration of the boulders’ presence in situ, have also been estimated from samples which have been kept refrigerated since their retrieval from the Moon. Natural and artificially produced microcraters have been studied with the following two main results : The dust-particle flux appears to have fallen off over a certain period of ca. 104-105 years (if the solar activity is assumed to be constant over that interval). Stones predominate in the large { ca . 2-10 um) diameter intervals, while irons outnumber stones at low diameters (ca . 1.0 um), in the micrometeorite flux incident on the Moon.

scholarly journals Does the lunar regolith contain secrets of the Solar System? Using the Moon as a cosmic witness plate

2009 ◽  
Vol 5 (S264) ◽  
pp. 475-477 ◽  
Author(s):  
David S. McKay ◽  
Louise Riofrio ◽  
Bonnie L. Cooper
Keyword(s):  
Solar System ◽  
Lunar Regolith ◽  
Lunar Soil ◽  
The Moon ◽  
System A ◽  
The Earth ◽  
Radiation History ◽  
History Of ◽  
Time Capsule ◽  
The Impact

AbstractThe lunar regolith (soil) has recorded a history of the early Moon, the Earth, and the entire solar system. A major goal of the developing lunar exploration program should be to find and play back existing fragments of that tape. By playing back the lunar tape, we can uncover a record of planetary bombardment, as well as solar and stellar variability. The Moon can tell us much about our place in the solar system and in the Universe. The lunar regolith has likely recorded the original meteoritic bombardment of Earth and Moon, a violent cataclysm that may have peaked around 4 GY, and the less intense bombardment occurring since that time. Decrease in bombardment allowed life to develop on Earth. This impact history is preserved as megaregolith layers, ejecta layers, impact melt rocks, and ancient impact breccias. The impact history for the Earth and Moon possibly had profound effects on the origin and development of life. Life may have arrived via meteorite transport from a more quiet body, such as Mars. The solar system may have experienced bursts of severe radiation from the Sun, other stars or from unknown sources. The lunar regolith has also recorded a radiation history in the form of implanted and trapped solar wind and solar flare materials and radiation damage. The Moon can be considered as a giant tape recorder containing the history of the solar system. Lunar soil generated by small impacts will be found sandwiched between layers of basalt or pyroclastic deposits. This filling constitutes a buried time capsule that is likely to contain well-preserved ancient regolith. Study of such samples will show us how the solar system has evolved and changed over time. The lunar recording can provide detailed snapshots of specific portions of solar and stellar variability.

scholarly journals A Compressive Sensing-Based Approach to Reconstructing Regolith Structure from Lunar Penetrating Radar Data at the Chang’E-3 Landing Site

2018 ◽  
Vol 10 (12) ◽  
pp. 1925 ◽  
Author(s):  
Kun Wang ◽  
Zhaofa Zeng ◽  
Ling Zhang ◽  
Shugao Xia ◽  
Jing Li
Keyword(s):  
Fourier Series ◽  
Compressive Sensing ◽  
Time Delays ◽  
Lunar Regolith ◽  
Landing Site ◽  
Radar Data ◽  
Lunar Rover ◽  
Signal Parameters ◽  
Lunar Environment ◽  
Scientific Systems

Lunar Penetrating Radar (LPR) is one of the important scientific systems onboard the Yutu lunar rover for the purpose of detecting the lunar regolith and the subsurface geologic structures of the lunar regolith, providing the opportunity to map the subsurface structure and vertical distribution of the lunar regolith with a high resolution. In this paper, in order to improve the capability of identifying response signals caused by discrete reflectors (such as meteorites, basalt debris, etc.) beneath the lunar surface, we propose a compressive sensing (CS)-based approach to estimate the amplitudes and time delays of the radar signals from LPR data. In this approach, the total-variation (TV) norm was used to estimate the signal parameters by a set of Fourier series coefficients. For this, we chose a nonconsecutive and random set of Fourier series coefficients to increase the resolution of the underlying target signal. After a numerical analysis of the performance of the CS algorithm, a complicated numerical example using a 2D lunar regolith model with clipped Gaussian random permittivity was established to verify the validity of the CS algorithm for LPR data. Finally, the compressive sensing-based approach was applied to process 500-MHz LPR data and reconstruct the target signal’s amplitudes and time delays. In the resulting image, it is clear that the CS-based approach can improve the identification of the target’s response signal in a complex lunar environment.

ROBOTS for MOON EXPLORATION

2021 ◽  
Author(s):  
Maxim Litvak ◽  
Igor Mitrofanov ◽  
Lev Zelenyi ◽  
Vladislav Tretyakov ◽  
Tatiana Kozlova ◽  
...  
Keyword(s):  
Lunar Regolith ◽  
Landing Site ◽  
Isotopic Analysis ◽  
Lunar Soil ◽  
Soil Samples ◽  
Robotic Arm ◽  
Successful Implementation ◽  
Polar Regions ◽  
Sample Collection ◽  
Water Ice

<p>Russian lunar program includes several landing missions of Luna-25, Luna-27, Luna-28 which should be implemented step by step to explore mineralogical, chemical, and isotopic compositions of the lunar polar regolith, search for volatile compounds, deliver soil samples to the Earth and prepare future manned expeditions to Moon.</p><p>The successful implementation of these missions requires employing of excavation and drilling of lunar regolith to the different depths with extraction of soil samples for the farther analysis (in situ or sample return).The first mission in row Luna-25 will be launched in October 2021 and landed at the area located north of Boguslawsky crater. This lander is equipped with the Lunar Manipulation Complex (LMC) – the robotic arm that should excavate lunar regolith (down to 5 – 25 cm) and deliver sample of lunar soil to the analytical instrumentation for the elemental and isotopic analysis. The robotic arm is already passed through the validation, functional and calibration tests in lunar-like conditions (low pressures and low temperatures) to imitate interaction with lunar soil simulant enriched with different content of water.</p><p>The Luna – 27 and Luna – 28 will be landed at southern polar regions (landing site selection is in progress). They will be equipped with Deep Drill Systems (DDS) to take samples of polar regolith enriched with water ice and other volatiles from 1-2 m depths. The DDS for Luna-27 , as part of the PROSPECT suit, shall be contributed by ESA. The DDS for Luna – 28 (the sample polar return mission) is being developed by Space Research Institute.In this presentation we report the results of ground tests with LMC units and DDS prototype.In addition to DDS, it is expected that Luna – 28 will carry a small sized lunokhod (~100 kg) to support sample collection and proceed with geological survey program (up to 30 km around the landing site per one year). The lunokhod will study elemental/isotopic/mineral composition of lunar regolith along rover traverse to estimate accessibility of lunar resources (first of all, water ice as a source of hydrogen and oxygen) applicable for potential industry utilization and support of manned expeditions. </p><p>The Russian lunar program assumes synergy of robotic and manned missions. Beyond Luna -25,27,28, it is expected that the next lunar missions will deliver to Moon surface heavy lunokhod, which will prepare the landing of the manned mission.  Finally, as part of testing program for manned lander (without cosmonauts), it is proposed to deliver multifunctional robotic equipment to support  the following arrival of cosmonauts. </p>

Effects of Load Type on the Mechanical Properties of the JLU Series Lunar Soil Simulant

2012 ◽  
Vol 204-208 ◽  
pp. 479-486 ◽  
Author(s):  
Jian Qiao Li ◽  
Rui Yang Shi ◽  
Meng Zou ◽  
Ling He ◽  
Yan Jing Yang ◽  
...  
Keyword(s):  
Shear Strength ◽  
Internal Friction ◽  
Lunar Regolith ◽  
Influence Factors ◽  
Friction Angle ◽  
Lunar Soil ◽  
Strength Characteristics ◽  
Natural State ◽  
Environmental Load ◽  
Lunar Rover

The pressure-sinkage characteristics and the shear-strength characteristics of lunar regolith are the important influence factors to the trafficability of lunar rover. The performance curves and parameters of JLU luanr soil simulant were obtained by pressure-sinkage tests and shear-strength tests in the ground gravity-environmental load (1g) and the lunar gravity-environmental load (1/6g). The results show that, for the pressure-sinkage characteristics, the compression-strength of the JLU-1 is strongest, followed by the JLU-3, and the JLU-2 is the weakest. In different load levels, the deformability index n increases as the bulk density increases. The kc increase as the state becoming more and more compact,The k of JLU-1 is the largest of all, followed by JLU-3 next, JLU-2 has the smallest.The load levels have no significant effect to the tendency of n, kc and k. For the shear-strength characteristics, the shear resistance of JLU-2 is the weakest. JLU-1 has the greatest cohesion c of the three lunar soil simulant, followed by JLU-3, the c of JLU-2 is the smallest.The c of the same lunar soil simulant in natural state is greater than it in soft state. Compared with JLU-1 and JLU-3, JLU-2 has the smallest internal friction angle .The influence of the load levels to the the cohesion c internal friction angel is not obvious. The  mesured in the lunar load is wider than it in the ground load. This study will supply fundamental reference and foundation on the research and optimization of the lunar rover traveling mechanism in the authentic lunar environment.

Tests on Effect of Gravity and Soil Density on Soil Cone Index

2013 ◽  
Vol 774-776 ◽  
pp. 528-531
Author(s):  
Rui Yang Shi ◽  
Jian Qiao Li ◽  
Meng Zou ◽  
Ling He ◽  
Shi Chao Fan ◽  
...  
Keyword(s):  
Lunar Regolith ◽  
Axial Direction ◽  
Lunar Soil ◽  
Foreign Object ◽  
Test Bed ◽  
Low Gravity ◽  
Lunar Rover ◽  
Gravity Condition ◽  
Walking Mechanism ◽  
Cone Index

The cone index is one of the important indicators that can describe the comprehensive physical characteristics of lunar regolith. Its closely related to the sink and sideslip of lunar rover and also has widely used in prediction the trafficability, adhesion property, tractive performance of lunar rover. Based on component method, a kind of low gravity simulator, the tiltable test-bed has been built. This study has got the stable low gravity along axial direction and measured the penetration resistance characteristics of JLU-2 in different gravity through tests. The results shows that the gravity environment has an obvious impact on the cone index of lunar soil simulant, CI values reduce with the decreasing of gravity environment. Namely, in the low gravity condition, it shows weaker resistance ability for a foreign object to penetrate into. The result has important application value of prepare, optimize and risk assessment in walking mechanism of lunar rover and the sampling mechanism.

scholarly journals North polar trough formation due to in-situ erosion as a source of young ice in mid-latitudinal mantles on Mars

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
J. Alexis P. Rodriguez ◽  
Kenneth L. Tanaka ◽  
Ali M. Bramson ◽  
Gregory J. Leonard ◽  
Victor R. Baker ◽  
...  
Keyword(s):  
Katabatic Wind ◽  
Spiral Pattern ◽  
Near Surface ◽  
Valuable Source ◽  
History Of ◽  
North Polar ◽  
Human Exploration ◽  
Erosional Event

AbstractThe clockwise spiral of troughs marking the Martian north polar plateau forms one of the planet’s youngest megastructures. One popular hypothesis posits that the spiral pattern resulted as troughs underwent poleward migration. Here, we show that the troughs are extensively segmented into enclosed depressions (or cells). Many cell interiors display concentric layers that connect pole- and equator-facing slopes, demonstrating in-situ trough erosion. The segmentation patterns indicate a history of gradual trough growth transversely to katabatic wind directions, whereby increases in trough intersections generated their spiral arrangement. The erosional event recorded in the truncated strata and trough segmentation may have supplied up to ~25% of the volume of the mid-latitude icy mantles. Topographically subtle undulations transition into troughs and have distributions that mimic and extend the troughs’ spiraling pattern, indicating that they probably represent buried trough sections. The retention of the spiral pattern in surface and subsurface troughs is consistent with the megastructure’s stabilization before its partial burial. A previously suggested warm paleoclimatic spike indicates that the erosion could have occurred as recently as ~50 Ka. Hence, if the removed ice was redeposited to form the mid-latitude mantles, they could provide a valuable source of near-surface, clean ice for future human exploration.

scholarly journals Development of a Field Deployable Firebrand Flux and Condition Measurement System

2020 ◽  
Author(s):  
Simone Zen ◽  
Jan C. Thomas ◽  
Eric V. Mueller ◽  
Bhisham Dhurandher ◽  
Michael Gallagher ◽  
...  
Keyword(s):  
Imaging Techniques ◽  
Time History ◽  
Infrared Camera ◽  
Thermal Conditions ◽  
Particle Characterization ◽  
Fire Dynamics ◽  
Rate Of Spread ◽  
New Instrument ◽  
History Of

AbstractA new instrument to quantify firebrand dynamics during fires with particular focus on those associated with the Wildland-Urban Interface (WUI) has been developed. During WUI fires, firebrands can ignite spot fires, which can rapidly increase the rate of spread (ROS) of the fire, provide a mechanism by which the fire can pass over firebreaks and are the leading cause of structure ignitions. Despite this key role in driving wildfire dynamics and hazards, difficulties in collecting firebrands in the field and preserving their physical condition (e.g. dimensions and temperature) have limited the development of knowledge of firebrand dynamics. In this work we present a new, field-deployable diagnostic tool, an emberometer, designed to provide measurement of firebrand fluxes and information on both the geometry and the thermal conditions of firebrands immediately before deposition by combining a visual and infrared camera. A series of laboratory experiments were conducted to calibrate and validate the developed imaging techniques. The emberometer was then deployed in the field to explore firebrand fluxes and particle conditions for a range of fire intensities in natural pine forest environments. In addition to firebrand particle characterization, field observations with the emberometer enabled detailed time history of deposition (i.e. firebrand flux) relative to concurrent in situ fire behaviour observations. We highlight that deposition was characterised by intense, short duration “showers” that can be reasonably associated to spikes in the average fire line intensity. The results presented illustrate the potential use of an emberometer in studying firebrand and spot fire dynamics.

scholarly journals In Situ exploration of the giant planets

2021 ◽  
Author(s):  
O. Mousis ◽  
D. H. Atkinson ◽  
R. Ambrosi ◽  
S. Atreya ◽  
D. Banfield ◽  
...  
Keyword(s):  
Solar System ◽  
Giant Planets ◽  
Atmospheric Composition ◽  
Formation History ◽  
History Of ◽  
Composition Structure ◽  
Galileo Probe ◽  
Probe Measurements

AbstractRemote sensing observations suffer significant limitations when used to study the bulk atmospheric composition of the giant planets of our Solar System. This impacts our knowledge of the formation of these planets and the physics of their atmospheres. A remarkable example of the superiority of in situ probe measurements was illustrated by the exploration of Jupiter, where key measurements such as the determination of the noble gases’ abundances and the precise measurement of the helium mixing ratio were only made available through in situ measurements by the Galileo probe. Here we describe the main scientific goals to be addressed by the future in situ exploration of Saturn, Uranus, and Neptune, placing the Galileo probe exploration of Jupiter in a broader context. An atmospheric entry probe targeting the 10-bar level would yield insight into two broad themes: i) the formation history of the giant planets and that of the Solar System, and ii) the processes at play in planetary atmospheres. The probe would descend under parachute to measure composition, structure, and dynamics, with data returned to Earth using a Carrier Relay Spacecraft as a relay station. An atmospheric probe could represent a significant ESA contribution to a future NASA New Frontiers or flagship mission to be launched toward Saturn, Uranus, and/or Neptune.

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