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NASA NTRS2007

Synchronous NDVI and Surface Air Temperature Trends in Newfoundland: 1982 to 2003

The northern regions of the earth are currently experiencing rapid change in temperature and precipitation. This region contains -40% of carbon stored in the world's soil which has accumulated from the last ice age (over 10,000 years ago). The carbon has remained to this point due to reduced decomposition from the short growing seasons and subfreezing temperatures. The influence of climate upon plant growth can have significant consequences to the carbon cycle balance in this region and could potentially alter and release this long term store of carbon to the atmosphere, resulting in a negative feedback enhancing climate warming. These changes have the potential to alter ecosystems processes, which impact human well being. This paper investigated a global satellite record of increases in vegetation growth from 1982 to 2003 developed at GSFC. It was found that, Newfoundland's vegetation growth during the 1990s exceeded global measurements. A number of potential causes were investigated to understand the mechanistic environmental drivers that could alter the productivity of this ecosystem. Possible drivers of change included: human influence of land use change on vegetation cover; changes in precipitation; temperature; cloud cover; snow cover; and growing season length. We found that humans had a minimal influence on vegetation growth in Newfoundland. Less than 6% of the island was logged during the investigation. We found a strong correlation of vegetation growth to a lengthening of the growing season of -9 and -17 days from 1982-1990 and 1991-1999. A distinct drop in plant growth and air temperature was found in 1990 to 1991 from the volcanic eruption of Mt. Pinatubo that reduced global surface air temperatures. These results document the influences of air temperature upon northern forest plant growth and the cooling effects of major volcanic eruptions in this ecological system.

Neigh, C. S. R.↗

NASA NTRS2008

Microwave Extraction of Lunar Water for Rocket Fuel

Nearly 50% of the lunar surface is oxygen, present as oxides in silicate rocks and soil. Methods for reduction of these oxides could liberate the oxygen. Remote sensing has provided evidence of significant quantities of hydrogen possibly indicating hundreds of millions of metric tons, MT, of water at the lunar poles. If the presence of lunar water is verified, water is likely to be the first in situ resource exploited for human exploration and for LOX-H2 rocket fuel. In-Situ lunar resources offer unique advantages for space operations. Each unit of product produced on the lunar surface represents 6 units that need not to be launched into LEO. Previous studies have indicated the economic advantage of LOX for space tugs from LEO to GEO. Use of lunar derived LOX in a reusable lunar lander would greatly reduce the LEO mass required for a given payload to the moon. And Lunar LOX transported to L2 has unique advantages for a Mars mission. Several methods exist for extraction of oxygen from the soil. But, extraction of lunar water has several significant advantages. Microwave heating of lunar permafrost has additional important advantages for water extraction. Microwaves penetrate and heat from within not just at the surface and excavation is not required. Proof of concept experiments using a moon in a bottle concept have demonstrated that microwave processing of cryogenic lunar permafrost simulant in a vacuum rapidly and efficiently extracts water by sublimation. A prototype lunar water extraction rover was built and tested for heating of simulant. Microwave power was very efficiently delivered into a simulated lunar soil. Microwave dielectric properties (complex electric permittivity and magnetic permeability) of lunar regolith simulant, JSC-1A, were measured down to cryogenic temperatures and above room temperature. The microwave penetration has been correlated with the measured dielectric properties. Since the microwave penetration depth is a function of temperature and frequency, an extraction system can be designed for water removal from different depths.

Ethridge, Edwin C.↗

NASA NTRS2008

Development of Lunar Highland REgolith Simulants, NU-LHT-1M,-2M

As part of a collaborative agreement between the U.S, Geological Survey (USGS) and NASA's Marshall Space Flight Center (MSFC) lunar highland simulants are being produced to support engineers and scientists in developing the technologies required to put a base on the moon by 2024. Two simulants have been produced to date: NU-LHT-1M and -2M (NASA/USGS-Lunar Highlands Type-l & 2 Medium-grained). Using starting material chiefly collected from the Stillwater Mine, Nye, MT, blending protocols were developed based on normative mineralogy calculated from average chemistry, for the Apollo 16 regolith. New technologies using a high temperature remotely coupled plasma melter were developed to generate both high quality and agglutinitic glasses that simulate the glassy components of the regolith. Detailed chemical, mineralogical and physical properties analysis of NU-LHT-1M indicate that it is overall a good surrogate for highlands lunar regolith (our new simulant LHT-2M has not be analyzed yet). The primary difference between 1M and 2M was the inclusion of trace mineralogy (phosphates and sulfide). Plans will also be presented on the future direction of the simulant project.

Stoeser, D. B.↗

NASA NTRS2008

Ares V and Future Very Large Launch Vehicles to Enable Major Astronomical Missions

The current NASA architecture intended to return humans to the lunar surface includes the Ares V cargo launch vehicle, which is planned to be available within a decade. The capabilities designed for Ares V would permit an 8.8-m diameter, 55 mT payload to be carried to Sun-Earth L1,2 locations. That is, this vehicle could launch very large optical systems to achieve major scientific goals that would otherwise be very difficult. For example, an 8-m monolith UV/visual/IR telescope appears able to be launched to a Sun-Earth L2 location. Even larger apertures that are deployed or assembled seem possible. Alternatively, multiple elements of a spatial array or two or three astronomical observatories might be launched simultaneously. Over the years, scientists and engineers have been evaluating concepts for astronomical observatories that use future large launch vehicles. In this presentation, we report on results of a recent workshop held at NASA Ames Research Center that have improved understanding of the science goals that can be achieved using Ares V. While such a vehicle uniquely enables few of the observatory concepts considered at the workshop, most have a baseline mission that can be flown on existing or near-future vehicles. However, the performance of the Ares V permits design concepts (e.g., large monolithic mirrors) that reduce complexity and risk.

Thronson, Harley A.↗

NASA NTRS2006

Mapping Weathering and Alteration Minerals in Virginia City, Nevada with AVIRIS and HyperSpecTIR

Situated on the east side of the Virginia Range, Virginia City (Figure 1) is the home of the historic Comstock mining district and was mined as a source of Au and Ag between 1859 and the 1960's, with numerous underground workings and small open pit operations. The Virginia Range consists mostly of Oligocene to Miocene volcanic rocks that overlie Mesozoic metamorphic rocks (Mzvs) and Cretaceous granodiorite (Kgd). Andesite to dacite flows, breccias and intrusives of the Alta Formation (Ta) (18-15 Ma) (Hudson, 2003) are overlain by intermediate volcanic, volcaniclastic and locally intrusive rocks of the Kate Peak Formation (Tk) (14.7-12 Ma) (Vikre, 1998; Hudson, 2003). Contemporaneous with the Alta Formation was the intrusion of the Davidson diorite (1 5.2 Ma) (Castor et al., 2002), which forms the bulk of Mt. Davidson just west of the town site.

HyperSpecTIR (HST)↗

NASA NTRS2008

The LHT (Lunar Highlands Type) Regolith Simulant Series

Three NU-LHT (NASA/USGS-Lunar Highlands Type) regolith simulants have been produced to date: NU-LHT-1M, -ID, and -2M. A fourth simulant is currently in production: NU-LHT-3C. The "M" (medium) designation indicates a simulant with a grain size of <1 mm, "D" (dust) a simulant with a grain size of <36 microns, and "C" (coarse) a simulant with a 10 cm maximum particle size. The composition of these simulants is based on a NASA average Apollo 16 regolith chemical composition, However, the mixing model used to create our simulants is based on cationic nonnative mineral proportions derived from the target chemical composition to approximate lunar modal mineralogy rather than chemical composition per se. Accordingly, the amount of plagioclase, pyroxenes, olivine, and trace minerals in the simulant crystalline fraction approximates that of the lunar regolith. We also added synthetic agglutinate in amounts approximate for low-medium regolith maturity. A pure glass fraction was also added to simulate other types of lunar glasses present in the regolith. In addition, the 3C simulant will include synthetic impact melt breccia clasts for the >1 cm particles. The bulk raw materials used to create these simulants include clinopyroxene-norite, anorthosite, hartzburgite and noritic mill waste from the Stillwater Mine, Nye, MT, and olivine from the Twin Sisters dunite, WA. Added trace minerals include beach sand ilmenite, chromite, synthetic p-tricaicium phosphate (whitiockite), gem grade fluor-apatite, and pyrite. The agglutinate, glasses, and synthetic breccia were designed and prepared at an industrial plasma melting facility in Boulder, CO, using Stillwater mill waste feedstock for the melt. These simulants do not include nanophase-feO. The M and C simulant grain size distribution (down to 0.4 microns) approximates that of Apollo 16 regolith and the regolith in general.

Stoeser, Douglas↗

NASA NTRS2009

An Operational Assessment of the MODIS False Color Composite with the Great Falls, Montana National Weather Service

The close and productive collaborations between the NWS Warning and Forecast Office (WFO) in Great Falls, MT and the Short Term Prediction and Research Transition (SPORT) Center at NASA/Marshall Space Flight Center have provided a unique opportunity for science sharing and technology transfer. In particular, SPoRT has provided a false color composite product derived from MODIS data, which is part of NASA's Earth Observing System. This product is designed to delineate snow and ice covered ground, bare ground and clouds. The Great Falls WFO has been a test bed of the MODIS false color composite as a tool in operations to monitor the development and dissipation of snow cover In particular, preliminary applications have shown that the product can be used to monitor snow cover in remote locations as well as ice in rivers. This information can lead to improved assessments of flooding potential during post event conditions where rapid melting and runoff are anticipated. The potential of this product on future geostationary satellites may substantially contribute to the NWS mission by providing enhanced situational awareness. The operational use of this product has been transitioned at WFO Great Falls through a process of product implementation, discussions with the service hydrologist and forecasters, and post event analysis. A concentrated assessment period from January to March, 2008 was initiated to investigate the impact of the MODIS false color product on WFO Great Falls' operations. This presentation will emphasize the impact the MODIS false color product had in the WFO's situational awareness and how best this information can be used to influence operational decisions.

Loss, GIna↗

NASA NTRS2009

Open-Access, Low-Magnetic-Field MRI System for Lung Research

An open-access magnetic resonance imaging (MRI) system is being developed for use in research on orientational/gravitational effects on lung physiology and function. The open-access geometry enables study of human subjects in diverse orientations. This system operates at a magnetic flux density, considerably smaller than the flux densities of typical other MRI systems, that can be generated by resistive electromagnet coils (instead of the more-expensive superconducting coils of the other systems). The human subject inhales air containing He-3 or Xe-129 atoms, the nuclear spins of which have been polarized by use of a laser beam to obtain a magnetic resonance that enables high-resolution gas space imaging at the low applied magnetic field. The system includes a bi-planar, constant-current, four-coil electromagnet assembly and associated electronic circuitry to apply a static magnetic field of 6.5 mT throughout the lung volume; planar coils and associated circuitry to apply a pulsed magnetic-field-gradient for each spatial dimension; a single, detachable radio-frequency coil and associated circuitry for inducing and detecting MRI signals; a table for supporting a horizontal subject; and electromagnetic shielding surrounding the electromagnet coils.

Mair, Ross W.↗

NASA NTRS2009

The Governing Processes and Timescales of Stratosphere-to-Troposphere Transport and its Contribution to Ozone in the Arctic Troposphere

We used the seasonality of a combination of atmospheric trace gases and idealized tracers to examine stratosphere-to-troposphere transport and its influence on tropospheric composition in the Arctic. Maximum stratosphere-to-troposphere transport of CFCs and O3 occurs in April as driven by the Brewer-Dobson circulation. Stratosphere-troposphere exchange (STE) occurs predominantly between 40 deg N to 80 deg N with stratospheric influx in the mid-latitudes (30-70 deg N) accounting for 67.81 percent of the air of stratospheric origin in the Northern Hemisphere extratropical troposphere. Transport from the lower stratosphere to the lower troposphere (LT) takes three months on average, one month to cross the tropopause, the second month to travel from the upper troposphere (UT) to the middle troposphere (MT), and the third month to reach the LT. During downward transport, the seasonality of a trace gas can be greatly impacted by wet removal and chemistry. A comparison of idealized tracers with varying lifetimes suggests that when initialized with the same concentrations and seasonal cycles at the tropopause, trace gases that have shorter lifetimes display lower concentrations, smaller amplitudes, and earlier seasonal maxima during transport to the LT. STE contributes to O3 in the Arctic troposphere directly from the transport of O3 and indirectly from the transport of NOy . Direct transport of O3 from the stratosphere accounts for 78 percent of O3 in the Arctic UT with maximum contributions occurring from March to May. The stratospheric contribution decreases significantly in the MT/LT (20.25 percent of total O3) and shows a very weak March.April maximum. Our NOx budget analysis in the Arctic UT shows that during spring and summer, the stratospheric injection of NO y-rich air increases NOx concentrations above the 20 pptv threshold level, thereby shifting the Arctic UT from a regime of net photochemical ozone loss to one of net production with rates as high as +16 ppbv/month.

Liang, Q.↗

NASA NTRS2010

Web-Based Interface for Command and Control of Network Sensors

This software allows for the visualization and control of a network of sensors through a Web browser interface. It is currently being deployed for a network of sensors monitoring Mt. Saint Helen s volcano; however, this innovation is generic enough that it can be deployed for any type of sensor Web. From this interface, the user is able to fully control and monitor the sensor Web. This includes, but is not limited to, sending "test" commands to individual sensors in the network, monitoring for real-world events, and reacting to those events

Wallick, Michael N.↗

NASA NTRS2010

Entry, Descent and Landing Systems Analysis Study: Phase 1 Report

DwyerCianciolo, Alicia M.↗

NASA NTRS2010

Entry, Descent and Landing Systems Analysis: Exploration Class Simulation Overview and Results

DwyerCianciolo, Alicia M.↗

NASA NTRS2010

Overview of the NASA Entry, Descent and Landing Systems Analysis Study

Zang, Thomas A.↗

NASA NTRS2010

Development of Thermal Protection Materials for Future Mars Entry, Descent and Landing Systems

Entry Systems will play a crucial role as NASA develops the technologies required for Human Mars Exploration. The Exploration Technology Development Program Office established the Entry, Descent and Landing (EDL) Technology Development Project to develop Thermal Protection System (TPS) materials for insertion into future Mars Entry Systems. An assessment of current entry system technologies identified significant opportunity to improve the current state of the art in thermal protection materials in order to enable landing of heavy mass (40 mT) payloads. To accomplish this goal, the EDL Project has outlined a framework to define, develop and model the thermal protection system material concepts required to allow for the human exploration of Mars via aerocapture followed by entry. Two primary classes of ablative materials are being developed: rigid and flexible. The rigid ablatives will be applied to the acreage of a 10x30 m rigid mid L/D Aeroshell to endure the dual pulse heating (peak approx.500 W/sq cm). Likewise, flexible ablative materials are being developed for 20-30 m diameter deployable aerodynamic decelerator entry systems that could endure dual pulse heating (peak aprrox.120 W/sq cm). A technology Roadmap is presented that will be used for facilitating the maturation of both the rigid and flexible ablative materials through application of decision metrics (requirements, key performance parameters, TRL definitions, and evaluation criteria) used to assess and advance the various candidate TPS material technologies.

Cassell, Alan M.↗

NASA NTRS2002

Advanced Spacecraft Designs in Support of Human Missions to Earth's Neighborhood

NASA's strategic planning for technology investment draws on engineering studies of potential future missions. A number of hypothetical mission architectures have been studied. A recent study completed by The NASA/JSC Advanced Design Team addresses one such possible architecture strategy for missions to the moon. This conceptual study presents an overview of each of the spacecraft elements that would enable such missions. These elements include an orbiting lunar outpost at lunar L1 called the Gateway, a lunar transfer vehicle (LTV) which ferries a crew of four from the ISS to the Gateway, a lunar lander which ferries the crew from the Gateway to the lunar surface, and a one-way lunar habitat lander capable of supporting the crew for 30 days. Other supporting elements of this architecture discussed below include the LTV kickstage, a solar-electric propulsion (SEP) stage, and a logistics lander capable of re-supplying the 30-day habitat lander and bringing other payloads totaling 10.3 mt in support of surface mission activities. Launch vehicle infrastructure to low-earth orbit includes the Space Shuttle, which brings up the LTV and crew, and the Delta-IV Heavy expendable launch vehicle which launches the landers, kickstage, and SEP.

Fletcher, David↗

NASA NTRS2011

Entry, Descent and Landing Systems Analysis: Exploration Feed Forward Internal Peer Review Slide Package

NASA senior management commissioned the Entry, Descent and Landing Systems Analysis (EDL-SA) Study in 2008 to identify and roadmap the Entry, Descent and Landing (EDL) technology investments that the agency needed to successfully land large payloads at Mars for both robotic and human-scale missions. Year 1 of the study focused on technologies required for Exploration-class missions to land payloads of 10 to 50 mt. Inflatable decelerators, rigid aeroshell and supersonic retro-propulsion emerged as the top candidate technologies. In Year 2 of the study, low TRL technologies identified in Year 1, inflatables aeroshells and supersonic retropropulsion, were combined to create a demonstration precursor robotic mission. This part of the EDL-SA Year 2 effort, called Exploration Feed Forward (EFF), took much of the systems analysis simulation and component model development from Year 1 to the next level of detail.

Dwyer Cianciolo, Alicia M.↗

NASA NTRS2011

Carbonaceous Chondrite-Rich Howardites; The Potential for Hydrous Lithologies on the HED Parent

Howardites, eucrites, and diogenites, collectively referred to as the "HED's", are a clan of meteorites thought to represent three different lithologies from a common parent body. Collectively they are the most abundant type of achondrites in terrestrial collections. Eucrites are crustal basalts and gabbros, diogenites are mostly orthopyroxenites and are taken to represent lower crust or upper mantle materials, and howardites are mixed breccias containing both lithologies and are generally regarded as derived from the regolith or near-surface. The presence of exogenous chondritic material in howardite breccias has long been recognized. As a group, howardites exhibit divergence in bulk chemistry from what would be produced by mixing of diogenite and eucrite end-members exclusively, a phenomenon most evident in elevated concentrations of siderophile elements. Despite this chemical evidence for chondritic input in howardite breccias, chondritic clasts have only been identified in a minority of samples, and typically at levels of only a few percent. Three recent Antarctic howardite finds, the paired Mt. Pratt (PRA) 04401 and PRA 04402 and Scott Glacier (SCO) 06040, are notable for their high proportion of carbonaceous chondrite clasts. PRA 04401 is particularly well-endowed, with large chondritic clasts occupying more than half of the modal area of the sections we examined. Previously only a few percent chondritic clasts had been observed to occur in howardites. PRA 04401 is the most chondrite-rich howardite known

Herrin, J. S.↗

NASA NTRS2011

Overview of the NASA Entry, Descent and Landing Systems Analysis Exploration Feed-Forward Study

Technology required to land large payloads (20 to 50 mt) on Mars remains elusive. In an effort to identify the most viable investment path, NASA and others have been studying various concepts. One such study, the Entry, Descent and Landing Systems Analysis (EDLSA) Study [1] identified three potential options: the rigid aeroshell, the inflatable aeroshell and supersonic retropropulsion (SRP). In an effort to drive out additional levels of design detail, a smaller demonstrator, or exploration feed-forward (EFF), robotic mission was devised that utilized two of the three (inflatable aeroshell and SRP) high potential technologies in a configuration to demonstrate landing a two to four metric ton payload on Mars. This paper presents and overview of the maximum landed mass, inflatable aeroshell controllability and sensor suite capability assessments of the selected technologies and recommends specific technology areas for additional work.

DwyerCianciolo, Alicia M.↗