Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington

Mars Pathfinder will place a single lander on the surface of Mars on July 4, 1997, following a December 1996 launch. As a result of the very successful first Mars Pathfinder Landing Site Workshop, the project has selected the Ares Vallis outflow channel in Chryse Planitia as the landing site. This location is where a large catastrophic outflow channel debouches into the northern lowlands. A second workshop and series of field trips, entitled Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington, were held in Spokane and Moses Lake, Washington. The purpose of the workshop was to provide a focus for learning as much as possible about the Ares Vallis region on Mars before landing there. The rationale is that the more that can be learned about the general area prior to landing, the better scientists will be able interpret the observations made by the lander and rover and place them in the proper geologic context. The field trip included overflights and surface investigations of the Channeled Scabland (an Earth analog for the martian catastrophic outflow channels), focusing on areas particularly analogous to Ares Vallis and the landing site. The overflights were essential for placing the enormous erosional and depositional features of the Channeled Scabland into proper three-dimensional context. The field trips were a joint educational outreach activity involving K-12 science educators, Mars Pathfinder scientists and engineers, and interested scientists from the Mars scientific community. Part 1 of the technical report on this workshop includes a description of the Mars Pathfinder mission, abstracts accepted for presentation at the workshop, an introduction to the Channeled Scabland, and field trip guides for the overflight and two field trips. This part, Part 2, includes the program for the workshop, summaries of the workshop technical sessions, a summary of the field trips and ensuing discussions, late abstracts of workshop presentations, reports on the education and public outreach activities carried out by the educators, and a list of the workshop and field trip participants

Predicting planetary rover mobility in reduced gravity using 1-g experiments

Traversing granular regolith, especially in reduced gravity environments, remains a potential challenge for wheeled rovers. Mitigating hazards for planetary rovers requires testing in representative environments, but direct Earth-based testing fails to account for the effect of reduced gravity on the soil itself. Here, experimental apparatus and techniques for reduced-gravity flight testing are used to systematically evaluate three existing Earth-based testing methods and develop guidelines for their use and interpretation: (i) reduced-weight testing, (ii) matching soil testing instrument response through soil simulant design, and (iii) granular scaling laws (GSL). Experimentation campaigns flying reduced-gravity parabolas, with soil and wheel both in lunar-g, have shown reductions in net traction of 20% or more and increases in sinkage of up to 40% compared to Earth-based testing methods (i) and (ii). Scaled-wheel testing, according to GSL (method iii) has shown better agreement with reduced-g tests (less than 10% error) and also tends to err on the side of conservative predictions. Limitations of GSL are investigated including a recently proposed cohesion constraint (that the wheel radius ratio must be the inverse of the gravity ratio) and the effects of wheel size and aspect ratio on GSL’s accuracy. It was found that the cohesion constraint can most likely be ignored for mildly cohesive soils such as lunar regolith. Limits on wheel sizes and aspect ratio variation are also proposed. The application of GSL to planetary rover testing is demonstrated through two studies undertaken in collaboration with NASA’s Jet Propulsion Laboratory. One study compares wheel designs for a skid-steer lunar rover in single-wheel tests scaled by GSL, demonstrating that diagonal grousers improve turning performance without requiring larger wheels. The second study involves application of GSL to the design of two reconfigurable test platforms for evaluating steep-terrain mobility performance. Another aspect of rover mobility testing—normal force control in single-wheel testbeds—is also investigated. An improved method for single-wheel testing, using a 4-bar mechanism, essentially eliminates normal force oscillations from frictional vertical sliders. Finally, guidelines for conducting and interpreting 1-g mobility tests for lunar rovers are presented, and potential avenues for future research are outlined

A Comparative Study of Natural Rehabilitation at a Former Mine Waste Site in the Carnon Valley, Cornwall

This study was carried out in the Carnon valley, which is located in Cornwall, south-west England. A river runs through the Carnon valley while former settlement ponds for processing tin and copper ore from the Wheal Jane mine are found on the floodplain. Tailings and waste rocks have accumulated on the floodplain to a height of about 6 meters. The valley is physically divided by a country road into the Middle valley and the Lower valley. Plant growth on tailings in the Middle valley, where tailings heaps were bulldozed, is visibly different from plant growth in the tailings and coarse waste rock observed in the Lower valley. The Lower valley, which features hummocks and hollows, appears to be less rehabilitated than the Middle valley. However, flora diversity in the Lower valley is considerably higher compared to the Middle valley, where a relatively homogeneous vegetation coverage is dominated by a few species. Other noticeable differences between the Lower and Middle valleys are a relative consistent soil compaction and the absence of visible ponds in the Middle valley. This research aims to identify the main drivers and limiting factors in the natural rehabilitation process and local biodiversity development in the middle and lower sections of the Carnon Valley. Through close year-round recording of natural plant species and colonies and habitat survey in the evolving terrain, it was attempted to correlate biota to progressive structural amelioration of the site. Species success was observed in relation to habitat evolution, restrictions imposed by residual toxicity of the former metal-mining terrain, advantages gained by artificial topographic diversity present on abandonment, and the stages reached in the dynamic progression of the combination of all of these features. By observing and recording the outcome of natural revegetation and identifying the impacts of abiotic factors, recommendations are made about the significance of such abandoned mine-sites in relation to ecological conservation value of such former disturbed land, and derive proposals for its onward management. We conclude that, on the site, complex interwoven processes occur of which we observe the state at one moment in time. The volume of data collected in the Carnon Valley is probably greater than available for any other known mine site of comparable history and size. While the data enabled inference of important biotic progressions, this study suggests that the 9 approaches may be applied to other abandoned mine sites, especially for assessment of natural attenuation of residual toxic legacies and ways to engineer future biotic rehabilitation patterns. The potential development of abandoned mine sites to re-establish natural biodiversity is thus recommended, together with a strategy for monitoring of future rehabilitation progression. The study consists of a field survey to record the present vegetation assemblage pattern, laboratory experiments to investigate soil features, data interpretation with statistical software, and evaluation of the interrelationship between emerging vegetation patterns and soil features. Extensive field work was undertaken within a one-year period, observing the highly heterogeneous vegetation community in a state of succession towards natural rehabilitation. The study generated up-to-date, detailed insight into year-round biodiversity development, notably of species diversity and seasonal stages of its development. Both transect surveys and quadrat surveys were carried out to capture general and spatial vegetation distribution variances. Fifty-seven quadrats, deemed to be representative, are surveyed in terms of plant species present and physical and chemical properties of the soil. While the natural vegetation of areas surrounding the valley has already been mapped, it is possible to build a factually-based picture of the progression of on-site species-assembly in relation to taxa that are, or are not, present in the surrounding landscape’s natural vegetation. This revealed that, out of a total of 87 species found in the valley, 9 are classified as very rare species in Cornwall. The presence of local rare species suggests the Carnon valley and other post-mining sites potentially have a significant ecological conservation value. This diversity and biotic taxonomic content of the former mine site highlights the importance of allowing natural biotic colonisation to continue in the wider interest of biodiversity conservation and utilisation of such sites as future biotic reserves. Vegetation survey revealed a host of unusual species assemblage settling on the contaminated soil, which is especially true in the community around ditches. The significantly high species richness and presence of rare species in the ditch community indicates the potential of an edge effect, which has a benefit for biodiversity and may be applied in mine site rehabilitation. The prominent high species richness in the core area (excluding the ditch community) of the Lower valley (75 species compared to 18 10 species in the Middle valley) emphasizes the value of heterogeneity. Bulldozing and human disturbance proved to be effective to improve vegetation coverage, but failed to promote biodiversity recovery. To investigate the effect of chemical contaminants on vegetation development, data is interpreted with ordination techniques such as redundancy analysis (RA) and principal component analysis (PCA). Both techniques indicate that arsenic and copper have a negative impact on vegetation development. Absorbed arsenic or phosphate exchangeable arsenic were found to be the most influential fractions of total arsenic in the soil which affect local species richness and biodiversity. Controlling arsenic fractionation is therefore an important strategy towards supporting vegetation recovery. The thesis postulates that sites with mine waste have special conservation value and that an edge effect may exist -from observing relatively high species diversity in zones along ditches. Water availability has great influence in ditch community development, but is remains unclear how it interacts with other factors to contribute to biodiversity development. The study shows the potential of natural rehabilitation, which should be considered as an option when planning for rehabilitation of former mine sites

Proceedings of the Lunar Materials Technology Symposium

The meeting was organized around a possible lunar outpost scenario, featuring industrial technologies, systems, and components applicable to the extraction, processing, and fabrication of local materials. Acknowledged space resources experts as well as investigators from outside the field whose knowledge could be applied to space development activities were brought together. Presentations came from a variety of specialists in fields such as minerals processing, environmental control, and communications. The sessions of the symposium were divided into the following areas: resource characterization, energy management, materials processing, environment control, and automation and communications

Concepts and Approaches for Mars Exploration

Abstracts describe missions, mission elements or experiments for consideration in the 2005-2020 time frame. Also the technologies and the support necessary to achieve the results are discussed.NASA Headquarters; Lunar and Planetary Institutehosted by Lunar and Planetary Institute ; sponsored by NASA Headquarters, Lunar and Planetary Institute ; convener Scott Hubbard

OEXP exploration studies technical report. Volume 3: Special reports, studies, and indepth systems assessments

The Office of Exploration (OEXP) at NASA has been tasked with defining and recommending alternatives for an early 1990's national decision on a focused program of manned exploration of the Solar System. The Mission analysis and System Engineering (MASE) group, which is managed by the Exploration Studies Office at the Johnson Space Center, is responsible for coordinating the technical studies necessary for accomplishing such a task. This technical report, produced by the MASE, describes the process used to conduct exploration studies and discusses the mission developed in a case study approach. The four case studies developed in FY88 include: (1) a manned expedition to PHOBOS; (2) a manned expedition to MARS; (3) a lunar surface observatory; and a lunar outpost to early Mars evolution. The final outcome of this effort is a set of programmatic and technical conclusions and recommendations for the following year's work

Analogue sites for Mars missions : MSL and beyond : March 5-6, 2011, The Woodlands, Texas

The goal of the workshop is to develop an inventory of analogue sites that have value to NASA's Mars Science Laboratory (MSL), the Mars 2018 missions, and Mars analogue missions by the Canadian Space Agency and other space agencies. There will be a strong focus on outstanding science questions and Mars habitability.National Aeronautics and Space Administration, Lunar and Planetary Instituteconveners, Mary Voytek ... [and others]PARTIAL CONTENTS: Rover Science Operations: Lessons from Rocky 7 and FIDO Field Experiments and Mars Exploration Rover Flight Operations / R.E. Arvidson--Small, Fresh Craters at the Nevada Test Site / L.E. Kirkland and K.C. Herr--Lava Tubes as Analog Repositories for Life, Geochemistry, and Climate Records on Mars / P. Boston, J.G. Blank, D.E. Northup, and M. Deans

Robotics 2010

Without a doubt, robotics has made an incredible progress over the last decades. The vision of developing, designing and creating technical systems that help humans to achieve hard and complex tasks, has intelligently led to an incredible variety of solutions. There are barely technical fields that could exhibit more interdisciplinary interconnections like robotics. This fact is generated by highly complex challenges imposed by robotic systems, especially the requirement on intelligent and autonomous operation. This book tries to give an insight into the evolutionary process that takes place in robotics. It provides articles covering a wide range of this exciting area. The progress of technical challenges and concepts may illuminate the relationship between developments that seem to be completely different at first sight. The robotics remains an exciting scientific and engineering field. The community looks optimistically ahead and also looks forward for the future challenges and new development