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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1996

A microelectronics approach for the ROSETTA surface science package

In relation to the Rosetta surface science package, the benefits of the application of advanced microelectronics packaging technologies and other output from the Mars environmental survey (MESUR) integrated microelectronics study are reported on. The surface science package will be designed to operate for tens of hours. Its limited mass and power consumption make necessary a highly integrated design with all the instruments and subunits operated from a centralized control and information management subsystem.

Sandau, Rainer↗
NASA NTRS1972

Adhesion, friction, wear, and lubrication research by modern surface science techniques.

The field of surface science has undergone intense revitalization with the introduction of low-energy electron diffraction, Auger electron spectroscopy, ellipsometry, and other surface analytical techniques which have been sophisticated within the last decade. These developments have permitted submono- and monolayer structure analysis as well as chemical identification and quantitative analysis. The application of a number of these techniques to the solution of problems in the fields of friction, lubrication, and wear are examined in detail for the particular case of iron; and in general to illustrate how the accumulation of pure data will contribute toward the establishment of physiochemical concepts which are required to understand the mechanisms that are operational in friction systems. In the case of iron, LEED, Auger and microcontact studies have established that hydrogen and light-saturated organic vapors do not establish interfaces which prevent iron from welding, whereas oxygen and some oxygen and sulfur compounds do reduce welding as well as the coefficient of friction. Interpretation of these data suggests a mechanism of sulfur interaction in lubricating systems.

Keller, D. V., Jr.↗
NASA NTRSDate not supplied

LASSIE: Legged Autonomous Surface Science In Analogue Environments

Roving planetary surface exploration missions operate using a pre-programmed plan that can limit the capability to effectively detect unexpected changes in terrain properties, adjust locomotion or sampling strategies, and autonomously identify scientifically valuable observations and adjust exploration strategies. In particular, the inability to measure and react to unexpected changes in regolith properties can negatively impact mission operations. The Mars Exploration Rover Spirit and InSight lander both experienced challenges related to understanding the geotechnical properties of regolith. The advancements in legged robotic platforms hold potential to address these challenges through greater sensitivity to changing surface properties. The Legged Autonomous Surface Science In Analogue Environments (LASSIE) project explores how legged roving platforms can use the leg motors to measure geotechnical properties of crusted and icy surface regolith and utilize those measurements to autonomously update the science operations plans. These tests will be performed in martian and lunar analog environments and also within lab settings.

K. R. Fisher↗
NASA NTRS2005

A Surface Science Paradigm for a Post-Huygens Titan Mission

With the Cassini-Huygens atmospheric probe drop-off mission fast approaching, it is essential that scientists and engineers start scoping potential follow-on surface science missions. This paper provides a summary of the first year of a two year design study which examines in detail the desired surface science measurements and resolution, potential instrument suite, and complete payload delivery system. Also provided are design concepts for both an aerial inflatable mobility platform and deployable instrument sonde. The tethered deployable sonde provides the capability to sample near surface atmosphere, sub-surface liquid (if it exists), and surface solid material. Actual laboratory tests of the amphibious sonde prototype are also presented.

Zimmerman, Wayne F.↗
NASA NTRS2004

A Surface Science Paradigm for a Post-Huygens Titan Mission

With the Cassini-Huygens atmospheric probe drop-off mission fast approaching, it is essential that scientists and engineers start scoping potential follow-on surface science missions. This paper provides a summary of the first year of a two year design study which examines in detail the desired surface science measurements and resolution, potential instrument suite, and complete payload delivery system. Also provided are design concepts for both an aerial inflatable mobility platform and deployable instrument sonde. The tethered deployable sonde provides the capability to sample nearsurface atmosphere, sub-surface liquid (if it exists), and surface solid material. Actual laboratory tests of the amphibious sonde prototype are also presented.

Cassini-Huygen↗
NASA NTRS2014

Human Mars Surface Science Operations

Human missions to the surface of Mars will have challenging science operations. This paper will explore some of those challenges, based on science operations considerations as part of more general operational concepts being developed by NASA's Human Spaceflight Architecture (HAT) Mars Destination Operations Team (DOT). The HAT Mars DOT has been developing comprehensive surface operations concepts with an initial emphasis on a multi-phased mission that includes a 500-day surface stay. This paper will address crew science activities, operational details and potential architectural and system implications in the areas of (a) traverse planning and execution, (b) sample acquisition and sample handling, (c) in-situ science analysis, and (d) planetary protection. Three cross-cutting themes will also be explored in this paper: (a) contamination control, (b) low-latency telerobotic science, and (c) crew autonomy. The present traverses under consideration are based on the report, Planning for the Scientific Exploration of Mars by Humans1, by the Mars Exploration Planning and Analysis Group (MEPAG) Human Exploration of Mars-Science Analysis Group (HEM-SAG). The traverses are ambitious and the role of science in those traverses is a key component that will be discussed in this paper. The process of obtaining, handling, and analyzing samples will be an important part of ensuring acceptable science return. Meeting planetary protection protocols will be a key challenge and this paper will explore operational strategies and system designs to meet the challenges of planetary protection, particularly with respect to the exploration of "special regions." A significant challenge for Mars surface science operations with crew is preserving science sample integrity in what will likely be an uncertain environment. Crewed mission surface assets -- such as habitats, spacesuits, and pressurized rovers -- could be a significant source of contamination due to venting, out-gassing and cleanliness levels associated with crew presence. Low-latency telerobotic science operations has the potential to address a number of contamination control and planetary protection issues and will be explored in this paper. Crew autonomy is another key cross-cutting challenge regarding Mars surface science operations, because the communications delay between earth and Mars could as high as 20 minutes one way, likely requiring the crew to perform many science tasks without direct timely intervention from ground support on earth. Striking the operational balance between crew autonomy and earth support will be a key challenge that this paper will address.

Bobskill, Marianne R.↗
NASA NTRS1994

Surface science capabilities from IMP spectral imaging

The Imager for Mars Pathfinder (IMP) had a single 12-position filter wheel for one of its two 'eyes'. Originally eight, and then nine, of these filters were optimized for surface science, and three narrow-band filters for atmospheric science. Because of some design revisions we will now have filter wheels on both sides. The wheels for right and left eyes are identical, 12 filter positions each, and rigidly linked to the same rotation shaft. There are now 13 surface filters, in addition to 5 for atmospheric observations. Details of all the filter positions are tabulated and approximate gaussian bandpasses for the 13 surface filters are shown.

Singer, Robert B.↗
NASA NTRS1988

Electronic materials high-T(sub c) superconductivity polymers and composites structural materials surface science and catalysts industry participation

The fifth year of the Center for Advanced Materials was marked primarily by the significant scientific accomplishments of the research programs. The Electronics Materials program continued its work on the growth and characterization of gallium arsenide crystals, and the development of theories to understand the nature and distribution of defects in the crystals. The High Tc Superconductivity Program continued to make significant contributions to the field in theoretical and experimental work on both bulk materials and thin films and devices. The Ceramic Processing group developed a new technique for cladding YBCO superconductors for high current applications in work with the Electric Power Research Institute. The Polymers and Composites program published a number of important studies involving atomistic simulations of polymer surfaces with excellent correlations to experimental results. The new Enzymatic Synthesis of Materials project produced its first fluorinated polymers and successfully began engineering enzymes designed for materials synthesis. The structural Materials Program continued work on novel alloys, development of processing methods for advanced ceramics, and characterization of mechanical properties of these materials, including the newly documented characterization of cyclic fatigue crack propagation behavior in toughened ceramics. Finally, the Surface Science and Catalysis program made significant contributions to the understanding of microporous catalysts and the nature of surface structures and interface compounds.

Source record↗
NASA NTRS2017

S-band Smallsat InSAR Constellation for Surface Deformation Science

Surface deformation studies using repeat-pass interferometric SAR have evolved into a powerful tool for geophysicists studying earthquake fault zones, volcanoes, ice sheet motion, and subterranean aquifers. Longer wavelengths (S-Band and L-Band) are preferred because they do not decorrelate as quickly as shorter wavelengths. Rapid revisit (1-3 days) is preferred because it allows the study of these phenomena at the timescales at which they commonly occur. Global access on such timescales is also required. Vector surface deformation measurements, taken from more than one direction, are a desired feature. This paper describes the conceptual architecture of a longer wave length, Smallsat SAR constellation of up to 12 satellites for rapid revisit surface deformation studies. The key to making such a constellation affordable is to lower launch costs, spacecraft costs, and instrument (SAR) costs. The first two objectives can be achieved using an ESPA-ring class, or Smallsat spacecraft. The third objective requires a SAR instrument sized to fit the mass and volume constraints imposed by such a spacecraft. Current state-of-the-art in miniaturization of electronics means that the radar transmit, receive and data handling functions can easily be implemented in a compact, low mass solution. The most significant challenge in designing a SAR to fit the Smallsat paradigm is in the dimensions of the antenna. The antenna sizing problem is addressed by adopting a smaller antenna than allowed by conventional SAR design rules. The baseline antenna design is simple, requiring no electronic beam-steering or beam-forming capability. Both reflectarray and microstrip patch antenna solutions are considered. The antenna structure is dual-purpose, to limit the overall system mass, with solar panels on the backplane providing power for the radar and spacecraft. The proposed solution easily accommodates radar squint angles of +/-30 degrees for repeat-pass interferometry measurements from multiple direct

Freeman, Anthony↗
NASA NTRS2010

Two-Phase Thermal Switching System for a Small, Extended Duration Lunar Surface Science Platform

This paper describes a novel thermal control system for the Warm Electronics Box (WEB) on board a small lunar surface lander intended to support science activities anywhere on the lunar surface for an extended duration of up to 6 years. Virtually all lander electronics, which collectively dissipate about 60 W in the reference mission, are contained within the WEB. These devices must be maintained below 323 K (with a goal of 303 K) during the nearly 15-earth-day lunar day, when surface temperatures can reach 390K, and above 263 K during the nearly 15-earth-day lunar night, when surface temperatures can reach 100K. Because of the large temperature swing from lunar day-to-night, a novel thermal switching system was required that would be able to provide high conductance from WEB to radiator(s) during the hot lunar day and low (or negligible) conductance during the cold lunar night. The concept that was developed consists of ammonia variable conductance heat pipes (VCHPs) to collect heat from WEB components and a polymer wick propylene loop heat pipe (LHP) to transport the collected heat to the radiator(s). The VCHPs autonomously maximize transport when the WEB is warm and autonomously shut down when the WEB gets cold. The LHP autonomously shuts down when the VCHPs shut down. When the environment transitions from lunar night to day, the VCHPs and LHP autonomously turn back on. Out of 26 analyzed systems, this novel arrangement was able to best achieve the combined goals of zero control power, autonomous operation, long life, low complexity, low T, and landed tilt tolerance.

Bugby, David C.↗
NASA NTRS2015

Problems at the Leading Edge of Space Weathering as Revealed by TEM Combined with Surface Science Techniques

Both transmission electron micros-copy (TEM) and surface analysis techniques such as X-ray photoelectron spectroscopy (XPS) were instrumen-tal in making the first characterizations of material generated by space weathering in lunar samples [1,2]. Without them, the nature of nanophase metallic Fe (npFe0) correlated with the surface of lunar regolith grains would have taken much longer to become rec-ognized and understood. Our groups at JSC and UVa have been using both techniques in a cross-correlated way to investigate how the solar wind contributes to space weathering [e.g., 3]. These efforts have identified a number of ongoing problems and knowledge gaps. Key insights made by UVa group leader Raul Barag-iola during this work are gratefully remembered.

Christoffersen, R.↗
NASA NTRS1986

Mars surface science requirements and plan

The requirements for obtaining geological, geochemical, geophysical, and meteorological data on the surface of Mars associated with manned landings were analyzed. Specific instruments were identified and their mass and power requirements estimated. A total of 1 to 5 metric tons, not including masses of drill rigs and surface vehicles, will need to be landed. Power associated only with the scientific instruments is estimated to be 1 to 2 kWe. Requirements for surface rover vehicles were defined and typical exploration traverses during which instruments will be positioned and rock and subsurface core samples obtained were suggested.

Blacic, J. D.↗
NASA NTRS1999

Venus Aerobot Surface Science Imaging System (VASSIS)

The VASSIS task was to design and develop an imaging system and container for operation above the surface of Venus in preparation for a Discovery-class mission involving a Venus aerobot balloon. The technical goals of the effort were to: a) evaluate the possible nadir-viewed surface image quality as a function of wavelength and altitude in the Venus lower atmosphere, b) design a pressure vessel to contain the imager and supporting electronics that will meet the environmental requirements of the VASSIS mission, c) design and build a prototype imaging system including an Active-Pixel Sensor camera head and VASSIS-like optics that will meet the science requirements. The VASSIS science team developed a set of science requirements for the imaging system upon which the development work of this task was based.

Greeley, Ronald↗
NASA NTRS2020

Artemis III Neutron Surface Science

This paper highlights lunar neutron science that can be performed in support of the Artemis 2024 mission within 6 degrees of the lunar south pole. There are two primary science goals: the characterization of the radiation environment, and secondly, inference of regolith composition including the presence of water. Characterizing the surface radiation environment is important for risk identification and mitigation during crewed lunar missions. The lunar surface radiation environment includes a unique neutron contribution. The relative contribution from neutrons is higher outside the shielding effects of Earth’s magnetic field, which the Moon experiences ~25% of its orbit. To evaluate the radiation risk to astronauts at the lunar surface, fast neutron measurements are needed. Neutrons are generated when galactic cosmic rays (GCR) collide with the lunar regolith and provide valuable elemental composition information about the near surface (< 1m). For the characterization of regolith composition, a low energy neutron spectrometer or counter can determine surface composition. This provides ground truth for orbital neutron data from the Lunar Reconnaissance Orbiter and Lunar Prospector missions.

Lunar science, Moon, geology, geophysics, neutron ↗
NASA NTRS2001

Carbon Nanotube Tip Probes: Stability and Lateral Resolution in Scanning Probe Microscopy and Application to Surface Science to Semiconductors

In this paper we present results on the stability and lateral resolution capability of carbon nanotube (CNT) scanning probes as applied to atomic force microscopy (AFM). Surface topography images of ultra-thin films (2-5 nm thickness) obtained with AFM are used to illustrate the lateral resolution capability of single-walled carbon nanotube probes. Images of metal films prepared by ion beam sputtering exhibit grain sizes ranging from greater than 10 nm to as small as approximately 2 nm for gold and iridium respectively. In addition, imaging stability and lifetime of multi-walled carbon nanotube scanning probes are studied on a relatively hard surface of silicon nitride (Si3N4). AFM images Of Si3N4 surface collected after more than 15 hrs of continuous scanning show no detectable degradation in lateral resolution. These results indicate the general feasibility of CNT tips and scanning probe microscopy for examining nanometer-scale surface features of deposited metals as well as non-conductive thin films. AFM coupled with CNT tips offers a simple and nondestructive technique for probing a variety of surfaces, and has immense potential as a surface characterization tool in integrated circuit manufacturing.

Nguyen, Cattien V.↗
NASA NTRS2010

Experimental Investigation of Space Radiation Processing in Lunar Soil Ilmenite: Combining Perspectives from Surface Science and Transmission Electron Microscopy

Energetic ions mostly from the solar wind play a major role in lunar space weathering because they contribute structural and chemical changes to the space-exposed surfaces of lunar regolith grains. In mature mare soils, ilmenite (FeTiO3) grains in the finest size fraction have been shown in transmission electron microscope (TEM) studies to exhibit key differences in their response to space radiation processing relative to silicates [1,2,3]. In ilmenite, solar ion radiation alters host grain outer margins to produce 10-100 nm thick layers that are microstructurally complex, but dominantly crystalline compared to the amorphous radiation-processed rims on silicates [1,2,3]. Spatially well-resolved analytical TEM measurements also show nm-scale compositional and chemical state changes in these layers [1,3]. These include shifts in Fe/Ti ratio from strong surface Fe-enrichment (Fe/Ti >> 1), to Fe depletion (Fe/Ti < 1) at 40-50 nm below the grain surface [1,3]. These compositional changes are not observed in the radiation-processed rims on silicates [4]. Several mechanism(s) to explain the overall relations in the ilmenite grain rims by radiation processing and/or additional space weathering processes were proposed by [1], and remain under current consideration [3]. A key issue has concerned the ability of ion radiation processing alone to produce some of the deeper- penetrating compositional changes. In order to provide some experimental constraints on these questions, we have performed a combined X-ray photoelectron spectroscopy (XPS) and field-emission scanning transmission electron (FE-STEM) study of experimentally ion-irradiated ilmenite. A key feature of this work is the combination of analytical techniques sensitive to changes in the irradiated samples at depth scales going from the immediate surface (approx.5 nm; XPS), to deeper in the grain interior (5-100 nm; FE-STEM).

Christoffersen, R.↗