Search NASA⌕ Search

SEARCH · Search NASA

Results for “VOLATILITY”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3

Feasibility and Definition of a Lunar Polar Volatiles Prospecting Mission

The recent Lunar Crater Observing and Sensing Satellite (LCROSS) mission has provided evidence for significant amounts of cold trapped volatiles in Cabeus crater near the Moon's south pole. Moreover, LRO/Diviner measurements of extremely cold lunar polar surface temperatures imply that volatiles can be stable outside or areas of strict permanent shadows. These discoveries suggest that orbital neutron spectrometer data point to extensive deposits at both lunar poles. The physical state, composition and distribution of these volatiles are key scientific issues that relate to source and emplacement mechanisms. These issues are also important for enabling lunar in situ resource utilization (ISRU). An assessment of the feasibility of cold-trapped volatile ISRU requires a priori information regarding the location, form, quantity, and potential for extraction of available resources. A robotic mission to a mostly shadowed but briefly .unlit location with suitable environmental conditions (e.g. short periods of oblique sunlight and subsurface cryogenic temperatures which permit volatile trapping) can help answer these scientific and exploration questions. Key parameters must be defined in order to identify suitable landing sites, plan surface operations, and achieve mission success. To address this need, we have conducted an initial study for a lunar polar volatile prospecting mission, assuming the use of a solar-powered robotic lander and rover. Here we present the mission concept, goals and objectives, and landing site selection analysis for a short-duration, landed, solar-powered mission to a potential hydrogen volatile-rich site.

Heldmann, Jennifer↗

Regolith Volatile Characterization (RVC) in RESOLVE

Resource investigation in the lunar poles is of importance to the potential impact of in-situ resource utilization (ISRU). The RESOLVE project developed a payload to investigate the permanently shadowed areas of the lunar poles and demonstrate ISRU technology. As a part of the RESOLVE project, the regolith volatile characterization (RVC) subsystem was designed to examine the release of volatiles from sample cores. The test sample was heated in the reactor to release the volatiles where they were analyzed with gas chromatography. Subsequently, the volatile sample was introduced into the lunar water resource demonstration (LWRD) subsystem where the released hydrogen and water were selectively captured. The objective of the Regolith Volatile Characterization (RVC) subsystem was to heat the crushed core sample and determine the desorption of volatile species of interest. The RVC subsystem encompasses the reactor and the system for volatile analysis. The system was designed to analyze H2, He, CO, CO2, N2, 02, CH4, H2S and H2O. The GC chosen for this work is a Siemens MicroSAM process GC with 3 columns and 8 TCD detectors. Neon was chosen as the carrier gas to enhance the analysis of hydrogen and helium.The limit of detection for the gases is approx.1000ppm for H2, CO. CO2 , N2, O2 and H2 S. The limit of detection for CH4 is approx.4000ppm and the water limit of detection is -10000 ppm with a sample analysis time of 2-3 minutes. These values (with the exception of water and H2S) were determined by dilution of a six gas mixture from Scott Gas (5% CO2, CO, O2, N2, 4% CH4 and H2) using mass flow controllers (MFC5). Water was calibrated at low levels using an in house relative humidity (RH) generator. H 2S and high concentrations of H2 were calibrated by diluting a pure stream of gas with MFCs. Higher concentrations of N2 and 02 were calibrated using Air again diluting with MFCs. There were three modification goals for the GC in EBU2 that would allow this process GC to be used in the field demo for RESOLVE. The first modification was to decrease the weight associated with the GC, this included eliminating the explosion proof case (Figure 1) and replacing it with a lightweight case as well as using an on board COPV tank for the neon carrier gas. The next goal was to add a second oven for the molecular sieve column to allow for dual temperature control during GC operation; the separation of hydrogen and helium is optimum at lower temperatures while the water analysis required higher temperatures creating a competing design requirement. The second oven also allows a lower limit of detection for water quantification and avoids the possibility of water condensing in the GC which could ruin the column characteristics. The final goal was to modify the column arrangement to optimize the system for our specific application. Figure 2 shows the internal details of the module optimized optimized for our field application. The modifications and performance of the gas analysis system will be discussed in detail.

Captain, Janine↗

An Overview of the Volatiles Investigating Polar Exploration Rover (VIPER) Mission

A critical goal to both science and exploration is to understand the form and location of lunar polar volatiles. The lateral and vertical distributions of these volatiles inform us of the processes that control the emplacement and retention of these volatiles, as well as helping to formulate in-situ resource utilization (ISRU) architectures. While significant progress has been made from orbital observations, measurements at a range of scales from centimeters to kilometers across the lunar surface are needed to generate adequate "volatile mineral models" for use in evaluating the resource potential of volatiles at the Moon. VIPER is a solar and battery powered rover mission designed to operate over multiple lunar days, traversing several kilometers as it continuously monitors for subsurface hydrogen and other surface volatiles. In specific thermal terrain types, including permanently shadowed terrain and locales that permit near-surface ice stability, subsurface samples will be examined for volatile content using a one-meter drill. This talk will provide an overview of the VIPER mission which is scheduled for flight to the Lunar South Pole in December 2022.

Colaprete, Anthony↗

Comparing the Volatile Contents of Basaltic Rocks Through the Inner Solar System

Volatiles in planetary interiors play important roles in magma genesis, crust formation, eruption style, and even habitability of planetary surfaces. Allan Treiman’s career has touched on volatiles in the Moon, Mars, HED-parent body, the Earth, Venus, and other planetary bodies through studies of igneous rocks, volatile-bearing igneous minerals within these rocks, and the secondary alteration products produced from these rocks and minerals. His seminal work in many of these fields has inspired our careers and many others in our field. Here, we will build on and summarize what we know of the volatile content of basaltic rocks in the inner solar system. Specifically, this talk will focus on using volatile-bearing minerals (amphibole and apatite) along with bulk compositions to constrain the pre-eruptive, and potentially predegassed, volatile content of the magma and their source regions. We will then use these estimates to compare the volatile content of the Earth, Moon, Mars, Venus, and Mercury and what open questions there are for each planetary body.

Justin Filiberto↗

Mars and earth - Origin and abundance of volatiles

An investigation is conducted concerning the factors which are responsible for the tenuous nature of the Martian atmosphere in comparison to the terrestrial atmosphere, taking into account new data obtained in connection with the Viking missions. It is found that Mars was poor in volatiles from the start and fell further behind earth by less complete outgassing, by extensive retrapping, and by the partial loss of lighter gases. Attention is given to noble gases on earth and Mars, the condensation of noble gases and other volatiles, the sources of earth's volatiles, the bulk composition of earth, the release of volatiles from earth, clues to the volatile endowment of Mars, an abundance table for Mars, a comparison of terrestrial and Martian conditions, isotopic data on noble gases, xenon-129 on Mars and earth, possibilities concerning the loss of an early Martian atmosphere, the evolution of the atmosphere of Mars, conditions in the case of planet Venus, and the reasons for the poorness of small planets in volatiles.

Anders, E.↗

Volatile elements in Allende inclusions

New data are presented on the relatively volatile elements (Mn, Na, and Cl) in coarse- and fine-grained Ca/Al-rich inclusions of different textures and mineralogy in the Allende meteorite. It is shown that the coarse-grained inclusions condensed from the solar nebula at high temperature and contained vanishingly small quantities of volatile elements at that time. Later, volatiles were added to these during the metamorphism of the Allende parent body. The fine-grained inclusions were also affected by the addition of volatiles during this metamorphism but, unlike the coarse-grained ones, they incorporated large amounts of volatiles when they condensed from the solar nebula, accounting for their higher volatile element contents.

Grossman, L.↗

Rusty rock 66095 - A paradigm for volatile-element mobility in highland rocks

The ultimate goals of Apollo 16 consortia investigations are related to a determination of the nature of the early crust of the moon, taking into account questions regarding the petrogenesis of highland breccias and melt-rocks. In addition to these potential objectives, the consortia study of 66095 has also the goal to provide information for an understanding of the origin of volatile elements. Since 66095 is the most volatile-rich sample returned by the Apollo missions and its elemental ratios mimic those in many Apollo 16 breccias, it was selected as a paradigm for the highland breccias. 66095 is a clast-laden, impact-melt breccia. The volatile-rich nature is manifest in the presence of rust, schreibersite, and minor volatile-bearing compounds, usually in association with native metal and/or troilite. Attention is given to aspects of petrography, mineral chemistry, major element chemistry, the volatile bearing phases, and the history of the volatiles starting with their ultimate origin.

Hunter, R. H.↗

Geomorphic clues to the Martian volatile inventory. 1: Flow ejecta blankets

There are classes of landforms whose presence on Mars is strongly suggestive, if not confirmatory, of the participation of volatiles, presumably water, in its geomorphic development: (1) valley networks, (2) outflow channels, (3) landslides, and (4) flow-ejecta blankets. The first two may represent landforms generated by the movement of volatiles from sources, while the latter two probably represent the dissipation of energy generated by forcing inputs (e.g., kinetic energy and gravity) modulated by volatiles. In many areas on Mars, all four processes have acted on the same lithologic materials and were influenced by the composition of those units, and possibility by the climatic regime at the time of their formation. One of the approaches discussed to this specific problem of landform genesis, and to the general problem of the present and past states of martian volatiles, is to attempt to constrain the distribution, amount, and history of available volatiles by using possible evidence of volatile participation expressed in the morphology of other related landforms (e.g., flow-ejecta blankets and landslides) coupled with physical models for landform genesis.

Pieri, D.↗

Planetary volatile history - Principles and practice

The history and evolution of planetary volatile inventories are considered. Planetary bulk volatile inventories are greatly affected by the distance from the preplanetary nebula center at which material accreted, with volatile contents increasing with increasing distance from the nebula center. Other significant factors include: planetary energetics and internal thermal history, planetary volatile sinks (including space), and operation of external variables such as solar energy on the transient, steady-state array of surface volatiles. The net result of all these processes is a volatile history that is itself a controlling factor in overall planetary history.

Fanale, F. P.↗

Analysis of laser extracted volatiles in carbonaceous chondrites

It is scientifically important to understand the composition of volatile compounds from interplanetary dust particles (IDPs) because they may be related to the primordial inventory of planetary materials which were necessary to provide environments conducive to the formation of life. The use of a laser microprobe to measure volatiles in IDPs was evaluated. Because primitive meteorites are thought to be closely related to IDPs, carbonaceous chondrites were used for the evaluation. Three sets of experiments were performed to determine the volatiles released from potential substrate materials, to analyze the volatiles released from matrices of bulk samples of carbonaceous chondrites, and to analyze volatiles released from approx. 100 to 200 micron meteorite particles to simulate IDPs. Aluminum appeared to be the best choice of substrate material. Mass ratios between carbonaceous chondrite matrices of Allende and Murchison show fair reproducibility with somewhat high uncertainties. Particles from the Orgueil, Murchison, and Allende meteorites produced measurable quantities of volatiles that appear to have mass spectra comparable to the bulk matrices.

Blanford, George E.↗

Potential of derived lunar volatiles for life support

The lunar regolith contains small quantities of solar wind implanted volatile compounds that have vital, basic uses for maintaining life support systems of lunar or space settlements. Recent proposals to utilize the helium-3 isotope (He-3) derived from the lunar regolith as a fuel for fusion reactors would result in the availability of large quantities of other lunar volatile compounds. The quantities obtained would provide the annual life support replacement requirements of 1150 to 23,000 inhabitants per ton of He-3 recovered, depending on the volatile compound. Utilization of the lunar volatile compounds for life support depends on the costs, in terms of materials and energy, associated with their extraction from the lunar regolith as compared to the delivery costs of these compounds from Earth resources. Considering today's conservative estimated transportation costs ($10,000 dollars per kilogram) and regolith mining costs ($5 dollars per ton), the life support replacement requirements could be more economically supplied by recovering the lunar volatile compounds than transporting these materials from Earth resources, even before He-3 will be utilized as a fusion fuel. In addition, availability of lunar volatile compounds could have a significant cost impact on maintaining the life support systems of the space station and a Mars base.

Bula, R. J.↗

Transportation of volatile elements in thermally evolving planetesimals: An important role of metallic iron

Ordinary chondrites are considered to have experienced thermal metamorphism in small bodies. We are interested in behaviors of volatile elements in such a kind of thermally evolving planetesimals. Volatile elements generally have high vapor pressures at high temperature. In porous bodies, with a high gas permeability, volatile elements are transported efficiently over a long range. Behavior of volatile elements transported by permeable gas flow can be handled by an equation whose form is similar to that of the equation of thermal diffusion. We can follow transportation of heats and volatile elements in planetesimals, when parameters in these equations, initial conditions and chemical behavior of volatile elements are given. Recently, we discovered that nitrogen in equilibrated H-chondrites is mainly trapped in taenite (f.c.c. Fe-Ni), probably dissolved in interstitial sites. Fegley suggests that metallic iron cannot trap nitrogen in the solar nebula gas due to its very low nitrogen partial pressure. Approximately 1 bar of nitrogen pressure is required to explain the nitrogen content in taenite. We may expect high nitrogen gas partial pressure (possibly produced by vaporization of nitrogen-bearing solids such as organic materials) at the interior of thermally evolving planetesimals. Kinetic behavior of nitrogen in taenite suggests that it can easily be equilibrated with the ambient nitrogen gas at temperatures of approximately 500 C or higher. We consider that nitrogen is trapped in taenite through a nitrogen redistribution process occurred during the thermal metamorphic event.

Hashizume, K.↗

Volatile transport on Venus and implications for surface geochemistry and geology

The high vapor pressure of volatile metal halides and chalcogenides (e.g., of Cu, Zn, Sn, Pb, As, Sb, Bi) at typical Venus surface temperatures, coupled with the altitude-dependent temperature gradient of approximately 8.5 K/km, is calculated to transport volatile metal vapors to the highlands of Venus, where condensation and accumulation will occur. The predicted geochemistry of volatile metals on Venus is supported by observations of CuCl in volcanic gases at Kilauea and Nyiragongo, and large enrichments of these and other volatile elements in terrestrial volcanic aerosols. A one-dimensional finite difference vapor transport model shows the diffusive migration of a thickness of 0.01 to greater than 10 microns/yr of moderately to highly volatile phases (e.g., metal halides and chalcogenides) from the hot lowlands (740 K) to the cold highlands (660 K) on Venus. The diffusive transport of volatile phases on Venus may explain the observed low emissivity of the Venusian highlands, hazes at 6-km altitude observed by two Pioneer Venus entry probes, and the Pioneer Venus entry probe anomalies at 12.5 km.

Brackett, Robert A.↗

Sources of Terrestrial Volatiles

Atmospheres are found enveloping those planets and satellites best able to hold them. The obvious conclusion is that volatile escape must have played nearly as great a role as volatile supply. A consequence of this view is that volatile supplies were probably much greater than the atmospheres that remain. The likeliest candidates are sources associated with the main events of planetary accretion itself such as volatile-rich planetesimals, or direct gravitational capture of nebular gases. Late asteroidal or cometary volatile-rich veneers are attractive, but they present quantitative difficulties. Comets in particular are inadequate, because the associated mass of stray comets that would have been scattered to the Oort Cloud or beyond is excessive. This difficulty applies to Uranus-Neptune planetesimals as well as to a putative massive early Kuiper Belt. Another potential problem with comets is that the D/H ratio in the three comets for which this has been measured is about twice that of Earth's oceans. Objects falling from a much augmented ancient asteroid belt remain a viable option, but timing is an issue: Can the depopulation of the asteroid belt be delayed long enough that it makes sense to talk of asteroids as a late veneer? Early accretion of asteroids as objects scattered into the maw of infant Earth makes more sense. Another appealing candidate population of volatile-rich objects for the inner solar system would be scattered planetesimals associated with the accretion of Jupiter, for two reasons: (1) Before there was Jupiter, there was no object in the solar system capable of expelling comets efficiently, and (2) the cross section of the inner solar system to stray objects was Greater when there were m many planetesimals.

Zahnle, K. J.↗

Assessing Requirements Volatility and Risk Using Bayesian Networks

There are many factors that affect the level of requirements volatility a system experiences over its lifecycle and the risk that volatility imparts. Improper requirements generation, undocumented user expectations, conflicting design decisions, and anticipated / unanticipated world states are representative of these volatility factors. Combined, these volatility factors can increase programmatic risk and adversely affect successful system development. This paper proposes that a Bayesian Network can be used to support reasonable judgments concerning the most likely sources and types of requirements volatility a developing system will experience prior to starting development and by doing so it is possible to predict the level of requirements volatility the system will experience over its lifecycle. This assessment offers valuable insight to the system's developers, particularly by providing a starting point for risk mitigation planning and execution.

Russell, Michael S.↗

Partitioning of U, Th and K Between Metal, Sulfide and Silicate, Insights into the Volatile-Content of Mercury

During the early stages of the Solar System formation, especially during the T-Tauri phase, the Sun emitted strong solar winds, which are thought to have expelled a portion of the volatile elements from the inner solar system. It is therefore usually believed that the volatile depletion of a planet is correlated with its proximity to the Sun. This trend was supported by the K/Th and K/U ratios of Venus, the Earth, and Mars. Prior to the MESSENGER mission, it was expected that Mercury is the most volatile-depleted planet. However, the Gamma Ray Spectrometer of MESSENGER spacecraft revealed elevated K/U and K/Th ratios for the surface of Mercury, much higher than previous expectations. It is possible that the K/Th and K/U ratios on the surface are not a reliable gauge of the bulk volatile content of Mercury. Mercury is enriched in sulfur and is the most reduced of the terrestrial planets, with oxygen fugacity (fO2) between IW-6.3 and IW-2.6 log units. At these particular compositions, U, Th and K behave differently and can become more siderophile or chalcophile. If significant amounts of U and Th are sequestered in the core, the apparent K/U and K/Th ratios measured on the surface may not represent the volatile budget of the whole planet. An accurate determination of the partitioning of these elements between silicate, metal, and sulfide phases under Mercurian conditions is therefore essential to better constrain Mercury's volatile content and assess planetary formation models.

Habermann, M.↗

Resource Prospector Instrumentation for Lunar Volatiles Prospecting, Sample Acquisition and Processing

Data gathered from lunar missions within the last two decades have significantly enhanced our understanding of the volatile resources available on the lunar surface, specifically focusing on the polar regions. Several orbiting missions such as Clementine and Lunar Prospector have suggested the presence of volatile ices and enhanced hydrogen concentrations in the permanently shadowed regions of the moon. The Lunar Crater Observation and Sensing Satellite (LCROSS) mission was the first to provide direct measurement of water ice in a permanently shadowed region. These missions with other orbiting assets have laid the groundwork for the next step in the exploration of the lunar surface; providing ground truth data of the volatiles by mapping the distribution and processing lunar regolith for resource extraction. This next step is the robotic mission Resource Prospector (RP).Resource Prospector is a lunar mission to investigate strategic knowledge gaps (SKGs) for in-situ resource utilization (ISRU). The mission is proposed to land in the lunar south pole near a permanently shadowed crater. The landing site will be determined by the science team with input from broader international community as being near traversable landscape that has a high potential of containing elevated concentrations of volatiles such as water while maximizing mission duration. A rover will host the Regolith Environment Science and Oxygen Lunar Volatile Extraction (RESOLVE) payload for resource mapping and processing. The science instruments on the payload include a 1-meter drill, neutron spectrometer, a near infrared spectrometer, an operations camera, and a reactor with a gas chromatograph-mass spectrometer for volatile analysis.

Lunar Crater↗

Evaluation of Volatile Species in Green Monopropellant Project

NASA is interested in green monopropellants to replace hydrazine in reaction control systems (RCSs). Some current NASA programs require reduced vapor pressure and low toxicity monopropellant (green) and superior performance (specific impulse and density) formulations. Earlier vapor phase studies of a candidate green monopropellant at the NASA White Sands Test Facility (WSTF) showed the presence of a volatile species that warranted further investigation. The purpose of this study was to further characterize the volatile species and to evaluate it. The evaluation was with respect to whether the volatile species was an impurity or how it is formed, and to use that information to examine whether its presence as an impurity can be eliminated during formulation. The evaluation also considered whether formation of the volatile impurity could be prevented while not compromising the propellant. To reduce variables associated with evaluation of the propellant formulation as a whole, a precursor to one of the individual components in the propellant formulation was subjected to a NASA Standard 6001B Flammability, Off-gassing, and Compatibility Requirements and Test Procedures "Determination of Off-gassed Products (Test 7)". Testing took place in the NASA WSTF Molecular Desorption and Analysis Laboratory. One gram of the precursor was placed in a flask within a specimen container. After thermal conditioning for 72 +/- 1 h at 50 +/- 3 deg C (122 +/- 5 deg F), the atmosphere inside the specimen container was analyzed for off-gassed compounds by cryotrap gas chromatography-mass spectrometry (GC-MS) and fixed sample loop GC-flame ionization detection (GC-FID). The specimen container used was glass to minimize potential catalytic surfaces. The identification of compounds was difficult due to the complexity of the vapor phase concentrations and overlapping chromatographic peaks and mass spectra. However, eleven compounds were specifically identified and five compounds or classes of compounds were reported as unidentified. Quantitation of most of the compounds, including unidentified compounds, was as methane. Quantitating compounds or classes of compounds that were detected but for which specific calibration is not established as methane is in accordance with the Test 7 standard protocol. The thermal decomposition temperature of the precursor was significantly higher than the test temperature. Based on thermal decomposition temperature and on an examination of the structure and chemistry of the identified volatile species, the presence of the volatile species appears to be chemically reasonable with respect to the propellant formulation and is at this time attributed to impurities. Further examination of the overall propellant formulation process (including the individual components' synthesis processes) and process quality control (including purity of reagents and possible decomposition reactions) is indicated.

Greene, Benjamin↗