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All sourcesNASA NTRSDOE OSTI
NASA NTRS2023

Contractor Support Building #7 Per- and Polyfluoroalkyl Substances (PFAS) Site Assessment Work Plan

This Work Plan documents the proposed field sampling activities for a per- and polyfluoroalkyl substances (PFAS) Site Assessment at the Contractor Support Building (CSB) #7 at Kennedy Space Center (KSC). The Work Plan provides a background of the historical activities that occurred at CSB #7, and the limited environmental investigations performed at CSB #7. The proposed Site Assessment activities at CSB #7 include the advancement of a soil lithologic boring to 60 feet below ground surface, the installation of a staff gauge in site surface water, perform direct push groundwater sampling at eight locations, and collect four surface water samples. Sampling details, depths, and locations are presented in the Work Plan. The Work Plan was presented to the KSC Remediation Team in the form of an Advance Data Package in February 2023. Following STRIVES approval, the CSB #7 PFAS Site Assessment Work Plan will be formally submitted to the Florida Department of Environmental Protection.

Howard Franklin Fowler↗
NASA NTRS1973

The moon as a proposed radiometric standard for microwave and infrared observations of extended sources.

Measured values of the average midnight and morning terminator infrared brightness temperatures of the central portion of the lunar disk can quite accurately determine the mean surface temperature despite likely horizontal and vertical inhomogeneities of the thermal properties of the lunar soil. These data together with laboratory measurements on lunar soil and in situ temperature measurements in and on the lunar surface lead to a mean surface temperature of 220.5 K plus or minus 2.5 per cent and a mean temperature 35 K hotter at a depth of 1 m. The monthly average brightness temperature is then estimated as a function of wavelength between 10 microns and 100 cm taking into account likely temperature dependencies of the thermal conductivity and loss tangent, and the variation of emissivity with wavelength.

Linsky, J. L.↗
NASA NTRS1973

Conjectures about the evolution of the moon.

The principal questions about the derivation of the lunar surface have not yet been settled: is it the surface left over from the process of accumulation of the moon, or is it a surface generated by magmatic processes on the moon and subsequently altered by further infall from outside. The evidence derived from many sources now favors the former. Seismic data suggest an absence of bedrock down to a depth of several kilometers, and instead a compacted powder only. The 'mascon' evidence can be understood as a consequence of major impacts in a deep porous layer. The great abundance of cosmic ray tracks in most soil samples demands a much greater cosmic ray dosage than present rates would cause in the age of the moon, unless the dust represented infallen material previously irradiated.

Gold, T.↗
NASA NTRS2011

Enhancing Global Land Surface Hydrology Estimates from the NASA MERRA Reanalysis Using Precipitation Observations and Model Parameter Adjustments

The Modern-Era Retrospective analysis for Research and Applications (MERRA) is a state-of-the-art reanalysis that provides. in addition to atmospheric fields. global estimates of soil moisture, latent heat flux. snow. and runoff for J 979-present. This study introduces a supplemental and improved set of land surface hydrological fields ('MERRA-Land') generated by replaying a revised version of the land component of the MERRA system. Specifically. the MERRA-Land estimates benefit from corrections to the precipitation forcing with the Global Precipitation Climatology Project pentad product (version 2.1) and from revised parameters in the rainfall interception model, changes that effectively correct for known limitations in the MERRA land surface meteorological forcings. The skill (defined as the correlation coefficient of the anomaly time series) in land surface hydrological fields from MERRA and MERRA-Land is assessed here against observations and compared to the skill of the state-of-the-art ERA-Interim reanalysis. MERRA-Land and ERA-Interim root zone soil moisture skills (against in situ observations at 85 US stations) are comparable and significantly greater than that of MERRA. Throughout the northern hemisphere, MERRA and MERRA-Land agree reasonably well with in situ snow depth measurements (from 583 stations) and with snow water equivalent from an independent analysis. Runoff skill (against naturalized stream flow observations from 15 basins in the western US) of MERRA and MERRA-Land is typically higher than that of ERA-Interim. With a few exceptions. the MERRA-Land data appear more accurate than the original MERRA estimates and are thus recommended for those interested in using '\-tERRA output for land surface hydrological studies.

Reichle, Rolf↗
NASA NTRS2012

Assessment and Enhancement of MERRA Land Surface Hydrology Estimates

The Modern-Era Retrospective analysis for Research and Applications (MERRA) is a state-ofthe-art reanalysis that provides, in addition to atmospheric fields, global estimates of soil moisture, latent heat flux, snow, and runoff for 1979-present. This study introduces a supplemental and improved set of land surface hydrological fields ("MERRA-Land") generated by re-running a revised version of the land component of the MERRA system. Specifically, the MERRA-Land estimates benefit from corrections to the precipitation forcing with the Global Precipitation Climatology Project pentad product (version 2.1) and from revised parameter values in the rainfall interception model, changes that effectively correct for known limitations in the MERRA surface meteorological forcings. The skill (defined as the correlation coefficient of the anomaly time series) in land surface hydrological fields from MERRA and MERRA-Land is assessed here against observations and compared to the skill of the state-of-the-art ERA-Interim (ERA-I) reanalysis. MERRA-Land and ERA-I root zone soil moisture skills (against in situ observations at 85 US stations) are comparable and significantly greater than that of MERRA. Throughout the northern hemisphere, MERRA and MERRA-Land agree reasonably well with in situ snow depth measurements (from 583 stations) and with snow water equivalent from an independent analysis. Runoff skill (against naturalized stream flow observations from 18 US basins) of MERRA and MERRA-Land is typically higher than that of ERA-I. With a few exceptions, the MERRA-Land data appear more accurate than the original MERRA estimates and are thus recommended for those interested in using MERRA output for land surface hydrological studies.

Reichle, Rolf H.↗
NASA NTRS2014

Infrared Spectral Observations While Drilling into a Frozen Lunar Simulant

Past and continuing observations indicate an enrichment of volatile materials in lunar polar regions. While these volatiles may be located near the surface, access to them will likely require subsurface sampling, during which it is desirable to monitor the volatile content. In a simulation of such activities, a multilayer lunar simulant was prepared with differing water content, and placed inside a thermal vacuum chamber at Glenn Research Center (GRC). The soil profile was cooled using liquid nitrogen. In addition to the soil, a drill and infrared (IR) spectrometer (~1600-3400 nm) were also located in the GRC chamber. We report the spectral observations obtained during a sequence where the drill was repeatedly inserted and extracted, to different depths, at the same location. We observe an overall increase in the spectral signature of water ice over the duration of the test. Additionally, we observe variations in the water ice spectral signature as the drill encounters different layers.

volatile content↗
NASA NTRS1978

Chemistry of orange/black soils from core 74001/2

Double core 74001/2 soils were studied. Bulk soils and the 90-150 micrometer and less than 20 micrometer size fractions of 13 soils from the core for both major and trace elements by instrumental neutron activation analysis were analyzed. The orange and black glassy soils in the core 74001/2 are homogeneous in composition and due to their unusual compositional characteristics probably have derived from a single source with the same composition. The top of the core has been reworked to a depth of about 5 cm. The reworked layer is marked by compositional differences in the first 3 cm which reflect the addition (at least 10%) of materials including mare basalt and a CaO-rich component. The maturity profile (I sub s/FeO) clearly indicates reworking depth of about 5 cm. It is likely that at least some of the ferro-magnetically active component (including agglutinitic glass) has been 'inherited' with the added material.

Blanchard, D. P.↗
NASA NTRS2023

Morpheus Test Area SWMU #119 Per- and Polyfluoroalkyl Substances (PFAS) Site Assessment Work Plan

This Work Plan documents the proposed field sampling activities for a per- and polyfluoroalkyl substances (PFAS) Site Assessment at the Morpheus Test Area (MTA) at Kennedy Space Center (KSC). The Work Plan provides a background of the historical activities that occurred at the MTA, and the limited environmental investigations performed at the MTA. The proposed Site Assessment activities at MTA includes the collection of soil samples from seven locations, the installation of a staff gauge in site surface water, the installation of four monitoring wells, perform direct push groundwater sampling at ten locations, and collect one surface water sample. Sampling details, depths, and locations are presented in the Work Plan. The Work Plan was presented to the KSC Remediation Team in the form of an Advance Data Package in February 2023. Following STRIVES approval, the SLF FRB PFAS Site Assessment Work Plan will be formally submitted to the Florida Department of Environmental Protection.

Howard Franklin Fowler↗
NASA NTRS1974

Lunar neutron capture as a tracer for regolith dynamics

The Apollo 17 Lunar Neutron Probe Experiment measured both the boron-10 neutron capture rate and the uranium-235 neutron-induced fission rate as a function of depth. Cd absorption gave a measure of the neutron energy spectrum. Comparisons of the results are made with theory, and good agreement is obtained for the magnitudes and depth dependences of the capture rates. While the low-energy neutron spectrum at depth agrees with theory, the spectrum near the peak of the flux profile is harder than predicted. In light of these results, several alternatives for interpreting the magnitude and uniformity of the neutron capture data from lunar surface soil samples are outlined. While none of the alternatives can be unquestionably defended or discarded, a surface layer mixing model is discussed in detail.

Burnett, D. S.↗
NASA NTRS1979

Theory and experiment for passive microwave remote sensing of snowpacks

Both the theory and experiment for the passive remote sensing of snow with microwave radiometers have been studied. The volume scattering effects of snow are accounted for by incorporating Mie scattering theory into a radiative transfer model. The theory is applied to the interpretation of experimental data obtained from various snow measurements. The spectral and angular dependences of the brightness temperatures are illustrated and show good agreement between the theory and experiment. Brightness temperatures as a function of snow depths are also interpreted and discussed. It is observed that as the snow depth increases, the brightness temperature increases when the subsurface is an aluminum plate due to the fact that the plate is cold and snow absorption induces a brightening effect and the brightness temperature decreases when the subsurface is soil due to the fact that snow scattering induces darkening effects.

Kong, J. A.↗
NASA NTRS1992

The mass balance of soil evolution on late Quaternary marine terraces, northern California

Mass-balance interpretation of a soil chronosequence provides a means of quantifying elemental addition, removal, and transformation that occur in soils from a flight of marine terraces in northern California. Six soil profiles that range in age from several to 240,000 yr are developed in unconsolidated, sandy-marine, and eolian parent material deposited on bedrock marine platforms. Soil evolution is dominated by (1) open-system depletion of Si, Ca, Mg, K, and Na; (2) open-system enrichment of P in surface soil horizons; (3) relative immobility of Fe and Al; and (4) transformation of Fe, Si, and Al in the parent material to secondary clay minerals and sesquioxides. Net mass losses of bases and Si are generally uniform with depth and substantial, in some cases approaching 100 percent; however, the rate of loss of each element differs markedly, causing the ranking of each by relative abundance to shift with time. Loss of Si from the sand fraction by dissolution and particle-size diminution, from about 100 percent to less than 35 percent over 240 ky, mirrors a similar gain in the silt and clay size fractions. The Fe originally present in the sand fraction decreases from greater than 80 percent to less than 10 percent, whereas the amount of Fe present in the clay and crystalline oxyhydroxide fractions increases to 25 percent and 70 percent, respectively.

Merritts, Dorothy J.↗
NASA NTRS2003

Mars Exploration Rovers as Virtual Instruments for Determination of Terrain Roughness and Physical Properties

The two 2003 Mars Exploration Rovers (MERs), in combination with the Athena Payload, will be used as virtual instrument systems to infer terrain properties during traverses, in addition to using the rover wheels to excavate trenches, exposing subsurface materials for remote and in-situ observations. The MERs are being modeled using finite element-based rover system transfer functions that utilize the distribution of masses associated with the vehicle, together with suspension and wheel dynamics, to infer surface roughness and mechanical properties from traverse time series data containing vehicle yaw, pitch, roll, encoder counts, and motor currents. These analyses will be supplemented with imaging and other Athena Payload measurements. The approach is being validated using Sojourner data, the FIDO rover, and experiments with MER testbed vehicles. In addition to conducting traverse science and associated analyses, trenches will be excavated by the MERs to depths of approximately 10-20 cm by locking all but one of the front wheels and rotating that wheel backwards so that the excavated material is piled up on the side of the trench away from the vehicle. Soil cohesion and angle of internal friction will be determined from the trench telemetry data. Emission spectroscopy and in-situ observations will be made using the Athena payload before and after imaging. Trenching and observational protocols have been developed using Sojourner results; data from the FIDO rover, including trenches dug into sand, mud cracks, and weakly indurated bedrock; and experiments with MER testbed rovers. Particular attention will be focused on Mini-TES measurements designed to determine the abundance and state of subsurface water (e.g. hydrated, in zeolites, residual pore ice?) predicted to be present from Odyssey GRS/NS/HEND data.

R E Arvidson↗
NASA NTRS1974

Chemical composition of rocks and soils at Taurus-Littrow

Seventeen soils and seven rock samples were analyzed for major elements, minor elements, and trace elements. Unlike the soils at previous Apollo sites, which showed little difference in composition at each collection area, the soils at Taurus-Littrow vary widely. Three soil types are evident, representative of (1) the light mantle at the South Massif, (2) the dark mantle in the valley, and (3) the surface material at the North Massif. The dark-mantle soils are chemically similar to those at Tranquillitatis. Basalt samples from the dark mantle are chemically similar although they range from fine to coarse grained. It is suggested that they originated from the same source but crystallized at varying depths from the surface.

Rose, H. J., Jr.↗
NASA NTRS1982

Subsurface valleys and geoarcheology of the eastern Sahara revealed by Shuttle radar

Previously unknown buried valleys, geologic structures, and possible Stone Age occupation sites have been revealed through the Shuttle Imaging Radar (SIR-A) penetration of the extremely dry Selima Sand Sheet, dunes and drift sand of the eastern Sahara. Radar penetration of dry sand and soils varies with the wavelength of the incident signals, which is 24 cm for the SIR-A system, as well as incidence angle and electrical properties of the material which are largely determined by moisture content. The calculated depth of radar penetration of dry sand and granules has been established to be 5 m on the basis of laboratory measurements of Selima Sand Sheet sample electrical properties. September 1982 field studies in Egypt have verified SIR-A signal penetration depths of at least 1 m in the Selima Sand Sheet and drift sand, and 2 m or more in sand dunes.

Mccauley, J. F.↗
NASA NTRS2004

Distribution of Near-Surface Ground Ice on Mars

During the course of this grant we made significant progress in our understanding of martian ground ice in areas of theoretical and laboratory research. We recently completed a manuscript comparing a new map of ground-ice stability with leakage neutron data for the southern hemisphere . In this manuscript we incorporated several improvements to a model of ground ice stability. We quantitatively compared measured epithermal-neutron flux with predicted ice-table burial depth and found that the observed distribution of ground ice is consistent with ice in diffusive equilibrium with the atmosphere. In addition to this theoretical study we have adapted an experimental apparatus, designed for measuring ice condensation in antarctic soils , to martian permafrost.

Mellon, Michael T.↗
NASA NTRSDate not supplied

Coupling of Dust Mineralogy to Radiation in NASA GISS ModelE: Impact Upon Dust Optical Properties and Direct Radiative Effect

Estimates of dust direct radiative effect (DRE) are still largely uncertain mainly due to the poor constraining of regional variations of dust absorption, whose known connection with mineral composition is still largely neglected by most Earth System Models. The inaccurate knowledge of soil mineralogy and insufficient measurements of dust physical and optical properties still present the main challenges for a proper representation of the dust-radiation interaction in climate models. We recently upgraded the coupling of dust minerals to shortwave radiation in the NASA GISS ModelE. In particular, we extended the interaction to online-calculated minerals and implemented two different mixing configurations: i) external mixing of three main mineral components and ii) internal mixing of all minerals, allowing a dynamic fraction of iron oxides. We used a semi-empirical approach for the optical calculations, mostly based on aerosol chamber measurements from natural soils, aiming to reduce the influence of uncertain assumptions on the optical properties and mixing state of individual minerals. In this contribution, we present the results of our first calculations of dust optical properties and DREs based on different mixing configurations of interactive minerals. We show the changes to dust optical depth and single scattering albedo, with respect to the control case using homogeneous dust composition, and the consequent global and regional variations in dust DREs at the top of atmosphere and at surface. We also compare the model optical properties with AERONET data, filtered to identify dust scenes. We find that accounting for the diverse properties of dust minerals modifies the pattern of regional dust absorption and therefore its impact upon climate. We also show that the mineralogy effect is sensitive to the assumed mixing state of minerals.

dust direct radiative effect↗
NASA NTRS2015

Crater Morphology in the Phoenix Landing Ellipse: Insights Into Net Erosion and Ice Table Depth

Icebreaker [1] is a Discovery class mission being developed for future flight opportunities. Under this mission concept, the Icebreaker payload is carried on a stationary lander, and lands in the same landing ellipse as Phoenix. Samples are acquired from the subsurface using a drilling system that penetrates into materials which may include loose or cemented soil, icy soil, pure ice, rocks, or mixtures of these. To avoid the complexity of mating additional strings, the drill is single-string, limiting it to a total length of 1 m.

Icebreaker mission↗
NASA NTRS1978

Mars - Remote spectral identification of H2O frost and mineral hydrate

A reflectance spectrum (0.62-2.6 microns) of Mars (integral disk) is obtained using a newly developed IR spectrometer at the 2.25 m telescope on Mauna Kea, Hawaii. Details of the instrument, observations, and data reduction are presented. Several distinct absorption features are evident that were apparently caused by H2O, but the positions and intensities of the features are quite unusual. In summary, the regolith is probably not as desiccated and dehydrated as the full disk reflectance spectrum and Viking soil analyses would suggest. The surface materials become desiccated and dehydrated as a result of solar UV effects and because of the relative adsorption and desorption rates during the strong diurnal cycling. There may be significant amounts of H2O at depth, and in the Solis Lacus region the H2O reservoir may extend to within a few centimeters of the surface. The Solis Lacus region may therefore be an important target for future Mars landing or sample return mission.

Huguenin, R. L.↗