Microwave Structure Construction Capability Year 1 Accomplishments
Explore the source record for details and available documents.
Microwave↗
Engineering topics
D. L. Rickman
Publications and source records attributed to D. L. Rickman.
The Complete Series of NU-LHT Lunar Simulants
The National Aeronautics and Space Administration (NASA) created the Constellation Program in response to the Bush Administration's A Renewed Spirit of Discovery: The President's Vision for U. S. Space Exploration, and the 2005 NASA Authorization Act from the United States Congress. As the Constellation program began its work, it was realized that the current supply of NASA lunar simulant (JSC-1) needed for testing of lunar surface system development, was almost exhausted. It was also realized that since global access was desired for future lunar exploration, both lunar mare and lunar highland simulants would be needed. Orbital Technologies Corporation (ORBITEC) was selected by NASA to produce a lunar mare simulant, which was referred to as JSC-1A, as it basically recreated the original JSC-1 using the same feedstock material from volcanic vents related to Merriam Crater near Flagstaff, AZ, and the same process by Dr. James Carter at the University of Texas at Dallas. For the lunar highlands, NASA collaborated with the United States Geological Survey (USGS) at the Denver Federal Center in Colorado, to develop and produce a new series of simulants.
J. E. Gruener↗
Measurements of Silicosis Factors in Lunar and Martian Simulants
Simulants are geologically complex materials that are developed to represent the physical and/or compositional characteristics of a planetary surface (e.g., a naturally occurring soil or regolith). There are dozens of commercially available simulants that have been developed over the years; each simulant exhibits unique physical, chemical, and mineralogical characteristics. Simulants are derived from either natural or synthetic sources (i.e., “feedstocks”) of glass, minerals, and rocks. These feedstock components are processed by crushing, pulverizing, melting, etc., and then combined in the appropriate proportions to represent a particular site, surface, or region (e.g., Lunar Highlands Regolith). The process of creating simulants therefore requires the mechanical breakdown and reincorporation of feedstock components which may contain crystalline silica minerals such as quartz, cristobalite, and tridymite. Certain crystalline silica particles of the respirable fraction (<10 μm in diameter) are of great concern; chronic and acute exposure to these respirable crystalline silica (RCS) can lead to permanent damage and scarring of lung tissue, incurable lung diseases (i.e., silicosis), lung cancer, COPD (chronic obstructive pulmonary disease), and kidney disease. Planetary simulants are used extensively as test materials in the in scientific and engineering communities (e.g., testing of dust mitigation technologies, in-situ resource utilization, rover mobility, hardware, soft goods etc.). As such, this assessment was developed to serve as a guide for simulant users, local Safety and Occupational Health professionals, and Industrial Hygienists to evaluate the risk of silicosis across a wide variety of Lunar and Martian simulants. The goal of these works is to ensure that those working with simulant can do so safely and with an informed understanding of potential health risks.
Lunar↗