SEARCH · Search NASA
Results for “extraterrestrial process”
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.
Publications of the exobiology program for 1990: A special bibliography
The Exobiology Program is an integrated program designed to investigate and understand those processes related to the origin, evolution, and distribution of life in the universe. The Exobiology Program is broad in scope, covering the following subject areas: cosmic evolution of biogenic compounds; prebiotic evolution; early evolution of life; evolution of advanced life; solar system exploration; search for extraterrestrial intelligence; planetary protection; and advanced programs in biological systems research. A listing of the 1990 publications resulting from research supported by the Exobiology Program is presented.
Meteors do not break exogenous organic molecules into high yields of diatomics
Meteoroids that dominate the Earth's extraterrestrial mass influx (50-300 microm size range) may have contributed a unique blend of exogenous organic molecules at the time of the origin of life. Such meteoroids are so large that most of their mass is ablated in the Earth's atmosphere. In the process, organic molecules are decomposed and chemically altered to molecules differently from those delivered to the Earth's surface by smaller (<50 microm) micrometeorites and larger (>10 cm) meteorites. The question addressed here is whether the organic matter in these meteoroids is fully decomposed into atoms or diatomic compounds during ablation. If not, then the ablation products made available for prebiotic organic chemistry, and perhaps early biology, might have retained some memory of their astrophysical nature. To test this hypothesis we searched for CN emission in meteor spectra in an airborne experiment during the 2001 Leonid meteor storm. We found that the meteor's light-emitting air plasma, which included products of meteor ablation, contained less than 1 CN molecule for every 30 meteoric iron atoms. This contrasts sharply with the nitrogen/iron ratio of 1:1.2 in the solid matter of comet 1P/Halley. Unless the nitrogen content or the abundance of complex organic matter in the Leonid parent body, comet 55P/Tempel-Tuttle, differs from that in comet 1P/Halley, it appears that very little of that organic nitrogen decomposes into CN molecules during meteor ablation in the rarefied flow conditions that characterize the atmospheric entry of meteoroids approximately 50 microm-10 cm in size. We propose that the organics of such meteoroids survive instead as larger compounds.
Development of a Piezoelectric Rotary Hammer Drill
The Piezoelectric Rotary Hammer Drill is designed to core through rock using a combination of rotation and high frequency hammering powered by a single piezoelectric actuator. It is designed as a low axial preload, low mass, and low power device for sample acquisition on future missions to extraterrestrial bodies. The purpose of this internship is to develop and test a prototype of the Piezoelectric Rotary Hammer Drill in order to verify the use of a horn with helical or angled cuts as a hammering and torque inducing mechanism. Through an iterative design process using models in ANSYS Finite Element software and a Mason's Equivalent Circuit model in MATLAB, a horn design was chosen for fabrication based on the predicted horn tip motion, electromechanical coupling, and neutral plane location. The design was then machined and a test bed assembled. The completed prototype has proven that a single piezoelectric actuator can be used to produce both rotation and hammering in a drill string through the use of a torque inducing horn. Final data results include bit rotation produced versus input power, and best drilling rate achieved with the prototype.
Twinned magnetite in granitic samples from the Siljan impact structure, Sweden
Impact cratering is a ubiquitous process throughout the solar system and has played a key role for the geologic evolution of Earth and other planets [1]. Magnetic anomalies are common characteristics of impact craters [2], so understanding how magnetite (Fe23+Fe2+O42-), an important magnetic carrier in both terrestrial and extraterrestrial rocks, is affected by shock waves, especially structurally and magnetically, is crucial. Magnetic minerals have been studied to gain insight into the geologic evolution of Mars, with specific focus including understanding the Martian crustal structure and the oxidization state of Martian rocks (e.g., [3,4,5]). Shock waves permanently alter the intrinsic magnetic properties of rocks (e.g., [6]), as do twinning in natural environments with less extreme P/T conditions [7]. In fact, pressure conditions induced by impacts have been suggested to explain demagnetization signatures observed around Martian impact basins [8]. It is still poorly understood what effects shock has on the crystallographic structure of magnetite and thus it’s intrinsic magnetic properties, and , how that affects the bulk magnetic properties of rocks (e.g., [9]). Limited experimental studies have investigated the effects of shock compression on magnetite, especially with the aim of describing crystallographic deformation (e.g., [9] and references therein). In this work we report preliminary results of an investigation of microstructures in magnetite, an “unconventional” mineral in shock studies, in granitic samples from the ca. 380 Ma ~52 km-in-diameter Siljan impact structure, located in south-central Sweden.
In Situ Measurements of Meteoric Ions
Extraterrestrial material is the source of metal ions in the Earth's atmosphere, Each year approx. 10(exp 8) kg of material is intercepted by the Earth. The origin of this material is predominantly solar orbiting interplanetary debris from comets or asteroids that crosses the Earth's orbit. It contains a very small amount of interstellar material. On occasion the Earth passes through enhanced amounts of debris associated with the orbit of a decaying comet. This leads to enhanced meteor shower displays for up to several days. The number flux of shower material is typically several times the average sporadic background influx of material. Meteoric material is some of the earliest material formed in the solar system. By studying the relative elemental abundances of atmospheric metal ions, information can be gained on the chemical composition of cometary debris and the chemical makeup of the early solar system. Using in situ sampling with rocket-borne ion mass spectrometers; there have been approximately 50 flights that made measurements of the metal ion abundances at attitudes between 80 and 130 km. It is this altitude range where incoming meteoric particles am ablated, the larger ones giving rise to visible meteor. displays. In several rocket measurements isotopic ratios of different atomic ion mass components and metal molecular ion concentrations have been determined and used to identify unambiguously the measured species and to investigate the processes controlling the metal ion distributions The composition of the Earth's ionosphere was first sampled by an ion mass spectrometer flown an a rocket in 1956. In 1958 a rocket-borne ion spectrometer identified, fbr the first time, a layer of metal ions near 95 km. These data were interpreted as evidence of an extraterrestrial rather than a terrestrial source. Istomin predicted: "It seems probable that with some improvement in the method that analysis of the ion composition in the E-region may be used for determining the chemical composition of those meteors which do not reach the ground. Particularly, we hope to get information about the composition difference between particles of different meteor showers and also sporadic and shower meteoroids". These visions categorized the aims of many subsequent rocket-borne ion mass spectrometer experiments in the lower ionosphere, Although the use such measurements to deduce the composition of different classes of meteoroids has not been successful, the past four decades of rocket observations have provided po%erful sets of data for advancing our understanding of meteor ablation, meteoric composition, metal neutral and ion chemistry as well as ionospheric dynamics.
Ilmenite beneficiation and high-precision analyses of extraterrestrial material
During the past year, work on characterizing lunar material that has the potential of becoming ilmenite lunar ore was performed. The important aspects of any such material are that it has abundant ilmenite and that the ilmenite be easily separated. The final result sought is a pure (greater than 99 percent ilmenite) concentrate that will be used as feed for the ilmenite reduction process. There are two types of starting material available on the moon. Solid rock (basalt or anorthosite) and regolith. Extensive literature reviews of ilmenite separation experiments were performed, and simulants (meteorites) were separated. It was concluded that, because of the large amounts of agglomerates, regolith may not be the best starting material for ilmenite beneficiation and that either basalts or anorthosites may be better. This is because no matter how finely the regolith is ground, it would not be possible to efficiently separate all the ilmenite. This hypotheses, however, needs to be tested with lunar material.
The Stable Isotope Fractionation of Abiotic Reactions: A Benchmark in the Detection of Life
One very important tool in the analysis of biogenic, and potentially biogenic, samples is the study of their stable isotope distributions. The isotope distribution of a sample depends on the process(es) that created it. One important application of the analysis of C & N stable isotope ratios has been in the determination of whether organic matter in a sample is of biological origin or was produced abiotically. For example, the delta C-13 of organic material found embedded in phosphate grains was cited as a critical part of the evidence for life in 3.8 billion year old samples. The importance of such analysis in establishing biogenicity was highlighted again by the role this issue played in the recent debate over the validity of what had been accepted as the Earth s earliest microfossils. These kinds of analysis imply a comparison with the fractionation that one would have seen if the organic material had been produced by alternative, abiotic, pathways. Could abiotic reactions account for the same level of fractionation? Additionally, since the fractionation can vary between different abiotic reactions, understanding their fractionations can be important in distinguishing what reactions may have been significant in the formation of different abiological samples (such as extraterrestrial samples). There is however, a scarcity of data on the fractionation of carbon and nitrogen by abiotic reactions. In order to interpret properly what the stable isotope ratios of samples tell us about their biotic or abiotic nature, more needs to be known about how abiotic reactions fractionate C and N. Carbon isotope fractionations have been studied for a few abiotic processes. These studies presumed the presence of a reducing atmosphere, focusing on reactions involving spark discharge, W photolysis of reducing gas mixtures, and cyanide polymerization in the presence of ammonia. They did find that the initial products showed a depletion in I3C with values in the range of a few per mil to as low as -60 % (potentially comparable to that which accompanies the biosynthesis of organic matter). We need to understand what kind of fractionations are observed with reactions under the non-reducing or mildly reducing conditions now thought to be present on the early Earth. While nitrogen is receiving increased attention as a tool for these kinds of analyses, almost nothing is known about the isotope fractionation that one would expect for abiotic sources of fixed/reduced nitrogen. This project will measure the fixation from a series of abiotic reactions that may have been present on the early Earth (and other terrestrial planets) and produced organic material that could have ended up in the rock record. The work will look at a number of reactions, under a non- reducing, or mildly reducing, atmosphere, covering sources of prebiotic organic C & N from shock heating, to photochemistry, to hydrothermal reactions. Some reactions that we plan to study are; Shock heating of a non-reducing atmosphere to produce CO and NO (in collaboration with Chris McKay), formation of formaldehyde (and related compounds) from COY the formation of ammonia from nitrogen oxides (ultimately from NO) by ferrous iron reduction, and the hydrothermal synthesis of compounds including the hydrocarboxylation/hydrocarbonylation reaction (in collaboration with George Cody), reactions of oxalate to form hydrocarbons and other oxygenated compounds and the formation of lipids from oxalic/formic acid (in collaboration with Tom McCollom), and reactions of carbon monoxide & carbon dioxide with N2, ammonia or nitritehitrate to form hydrogen cyanide, nitriles, ammonia/amines and nitrous
Project Cyclops: a Design Study of a System for Detecting Extraterrestrial Intelligent Life
The requirements in hardware, manpower, time and funding to conduct a realistic effort aimed at detecting the existence of extraterrestrial intelligent life are examined. The methods used are limited to present or near term future state-of-the-art techniques. Subjects discussed include: (1) possible methods of contact, (2) communication by electromagnetic waves, (3) antenna array and system facilities, (4) antenna elements, (5) signal processing, (6) search strategy, and (7) radio and radar astronomy.
Study for identification of beneficial uses of space, phase 1. Volume 1: Executive summary
The technological effects of the Space Shuttle Program are considered in terms of the development of improved products, processes, and services aimed at benefitting the public from economic and sociological points of view. As such, an outline is provided for a large number of private organizations to suggest and identify specific areas of research and development which can most effectively be exploited in an extraterrestrial environment.
Visualization of Microbial Biomarkers by Scanning Electron Microscopy
We are developing tools to link the biochemical structure of selected biomarkers with putative biogenic structures observed in mineralized samples. The detection of evidence of life on Mars and other planets will rely on methods that can discriminate compounds formed exclusively by living organisms. While biogenic compounds, such as amino acids and nucleotides have been discovered in extraterrestrial sources, such as meteorites and comets, their formation can be explained by abiotic means. The formation of cellular structures, or more elaborate organic molecules, such as complex lipids, proteins or nucleic acids, however, is strongly correlated to the presence of even the most primitive life processes. Recent evidence lends support to the hypothesis that life may have once existed on Mars. Carbonate globules and ppm concentrations of polycyclic aromatic hydrocarbons (PAHs) have been described in ALH84001, a meteorite originating from Mars ejecta captured by Earth over 13,000 years ago. The localized high concentration of PAHs that follow an increasing gradient from the intact fusion crust towards the interior corresponds to microgram quantities of hydrocarbon. Even though ALH84001 and other similar meteorites have withstood the forces capable of ejecting rock through Mars' escape velocity, upon entering Earth's atmosphere, their core temperatures are likely not to have been raised significantly, as evidenced by the survival of remanent magnetic signatures. Ideal biomarkers of ancient or modern biological life would include molecules that are (or were) pervasive and highly resistant to degradation. Also, requisite methods of detection should be simple, extremely sensitive and broadly inclusive (NASA SP-530). Lipopolysaccharide (LPS), peptidoglycan or pseudopeptidoglycan and beta-glucan are microbial cell wall components which together cover the entire microbial spectrum of eubacteria, archea and fungi. They are all remarkably resistant to thermal degradation. Fortunately, many antimicrobial defense systems of higher organisms require sensitive detection to combat microbial pathogens. We employ here the primitive immune system of the evolutionarily ancient horseshoe crab, Limulus polyphemus. This species relies on multi-enzyme signal amplification detection of cell wall molecules and they can be applied to the development of useful detectors of life. An extension of this work includes the visualization of microbial signatures by labeling LAL components with chromogenic or electron dense markers. The protein Limulus Anti-LPS Factor (LALF) has an extremely high affinity for LPS. By coupling LALF binding with colloidal gold labels we demonstrate a correlation of the structures visible by electron microscopy with biochemical evidence of microbial cell wall materials. Pure silica particles were mixed with cultures of E. coli (10(exp 6) cfu/mL). Samples were washed sequentially with buffered saline, LALF, antibody to LALF and finally colloidal gold-labeled Protein A. Negative controls were not exposed to E. coli but received identical treatment otherwise. Samples were coated with carbon and imaged on a JEOL JSM-840 scanning electron microscope with LaB6 source in the back scatter mode with the JEOL annular back scatter detector. 20 nm-scale black spots in this contrast-reversed image originate from electrons back-scattered by gold atoms. Negative controls did not give any signal. Future work will expand application of this technique to soil simulants and mineralized rock samples.
Lunar Polar In Situ Resource Utilization (ISRU) as a Stepping Stone for Human Exploration
A major emphasis of NASA is to extend and expand human exploration across the solar system. While specific destinations are still being discussed as to what comes first, it is imperative that NASA create new technologies and approaches that make space exploration affordable and sustainable. Critical to achieving affordable and sustainable exploration beyond low Earth orbit (LEO) are the development of technologies and approaches for advanced robotics, power, propulsion, habitats, life support, and especially, space resource utilization systems. Space resources and how to use them, often called In-Situ Resource Utilization (ISRU), can have a tremendous beneficial impact on robotic and human exploration of the Moon, Mars, Phobos, and Near Earth Objects (NEOs), while at the same time helping to solve terrestrial challenges and enabling commercial space activities. The search for lunar resources, demonstration of extraterrestrial mining, and the utilization of resource-derived products, especially from polar volatiles, can be a stepping stone for subsequent human exploration missions to other destinations of interest due to the proximity of the Moon, complimentary environments and resources, and the demonstration of critical technologies, processes, and operations. ISRU and the Moon: There are four main areas of development interest with respect to finding, obtaining, extracting, and using space resources: Prospecting for resources, Production of mission critical consumables like propellants and life support gases, Civil engineering and construction, and Energy production, storage, and transfer. The search for potential resources and the production of mission critical consumables are the primary focus of current NASA technology and system development activities since they provide the greatest initial reduction in mission mass, cost, and risk. Because of the proximity of the Moon, understanding lunar resources and developing, demonstrating, and implementing lunar ISRU provides a near and early opportunity to perform the following that are applicable to other human exploration mission destinations: Identify and characterize resources, how they are distributed, and the material, location and environment in which they are found; Demonstrate concepts, technologies, and hardware that can reduce the cost and risk of human exploration beyond Earth orbit; Use the Moon for operation experience and mission validation for much longer missions that are farther from Earth Develop and evolve ISRU to support sustained, economical human presence beyond Earth's orbit, including promoting space commercialization As Table 1 depicts, the Moon provides environments and resources applicable to Mars and NEOs. Two lunar ISRU resource and product pathways that have notable synergism with NEO, Phobos/Demos, and Mars ISRU are oxygen/metal extraction from regolith, and water/volatile extraction from lunar polar materials. To minimize the risk of developing and incorporating ISRU into human missions, a phased implementation plan is recommended that starts with prospecting and demonstrating critical technologies on robotic and human missions, then performing pilot scale operations (in non-mission critical roles) to enhance exploration mission capabilities, leading to full utilization of space resources in mission critical roles. Which lunar ISRU pathway is followed will depend on the results of early resource prospecting/proof-ofconcept mission(s), and long-term human exploration plans.
Detection of acetylene in the infrared spectrum of comet Hyakutake
Comets are rich in volatile materials, of which roughly 80% (by number) are water molecules. Considerable progress is being made in identifying the other volatile species, the abundances of which should enable us to determine whether comets formed primarily from ice-covered interstellar grains, or from material that was chemically processed in the early solar nebula. Here we report the detection of acetylene (C2H2) in the infrared spectrum of comet C/1996 B2 (Hyakutake). The estimated abundance is 0.3-0.9%, relative to water, which is comparable to the predicted solid-phase abundance in cold interstellar clouds. This suggests that the volatiles in comet Hyakotake may have come from ice-covered interstellar grains, rather than material processed in the accretion disk out of which the Solar System formed.
Recent landforms at Kilaueu Volcano: A selected photographic compliation
Recent eruptive activity at Kilauea has produced great changes in the landscape, modifying old landforms and creating new ones. Some of these landforms are observed fairly commonly in basaltic terrains, but many had rarely, if ever, been observed before in the process of development. The 1969-74 Mauna Ulu eruptions have provided the first historic opportunity at Kilauea to witness and record the development of features associated with flank activity of long duration. The photographs of new or modified landforms in this compilation place special emphasis on possible extraterrestrial analogs.
Comets and the origins and evolution of life; Proceedings of the Conference, Univ. of Wisconsin, Eau Claire, Sept. 30-Oct. 2, 1991
Papers are presented on comets and the formation of biochemical compounds on the primitive earth; the cometary origin of carbon, nitrogen, and water on the earth; comets as a possible source of prebiotic molecules; comet impacts and chemical evolution on the bombarded earth; and cometary supply of terrestrial organics (lessons from the K/T and the present epoch). Other papers are on a computational study of radiation chemical processing in comet nuclei, the origin of the polycyclic aromatic hydrocarbons in meteorites, the fate of organic matter during planetary accretion (preliminary studies of the organic chemistry of experimentally shocked Murchison meteorite), recent observations of interstellar molecules (detection of CCO and a limit on H2C3O), terrestrial and extraterrestrial sources of molecular monochirality, and dark matter in the solar system (hydrogen cyanide polymers).
Search for Organic Nanoglobules in Carbonaceous Chondrites Using Microtomography
Primitive solar materials have various organic matters. In recent years, novel organic materials called organic nanoglobules of a few hundred micrometers in typical size were discovered in carbonaceous chondrites, IDPs, and comet 81P/Wild 2. The organic globules are spherical shape and in many cases with hollow structures. Composition of the globules are mainly aromatic carbon. The isotopic anomalies of SD and 6N 15 observed in the globules indicate that they were formed from photochemical reaction to ice particles at very low temperature environment, such as molecular clouds or outer protosolar disk. Aqueous alteration of organic matters and the gamma-ray irradiation to PAH are also suggested as alternative possible formation processes. If the globules are made from organic ice particles, the hollow regions of the globules are suggested to be once filled with volatile H20-rich organic ices, while if they were formed by aqueous alteration, the hollow regions should be filled with a fluid which caused the aqueous alteration. However, fluids in the globules have not been detected so far in the previous studies. If fluids were originally preserved in the hollows, they might be lost during destructive processes of sample separation or preparation for TEM observation. X-ray computed tomography (CT) is a nondestructive method which can determine 3-D internal structures of objects. SR (synchrotron radiation)-based imaging microtomography can give submicron spatial resolution [8] and was applied to micro textures in extraterrestrial materials, such as cometary grains captured by the Stardust mission [9]. If organic globules are observed non-destructively in carbonaceous chondrites by tomography, we can check the presence of fluids in the hollows. If fluids are preserved, we may analyze chemical and isotopic compositions of the fluids. The purpose of this study is to observe organic nanoglobules using imaging tomography for future analysis.
Volatile Abundances of Apatite in CK and R Chondrites: Implications for Apatite Volatile Records in Oxidized and Thermally Altered Chondrite Parent Bodies
The mineral apatite [Ca5(PO4)3(F,Cl,OH)] is one of the primary mineralogical reservoirs for phosphorus on Earth, and it is a common phosphate mineral within a broad range of extraterrestrial samples. Naturally occurring apatite hosts F, Cl, and OH as essential structural constituents, and all three make up the apatite endmembers fluorapatite, chlorapatite, and hydroxylapatite, respectively. The presence of apatite in chondrite parent bodies indicates that apatite may hold a record of volatiles and their associated processes during the nascent stages of planetesimal formation and evolution.
Titan: a laboratory for prebiological organic chemistry
When we examine the atmospheres of the Jovian planets (Jupiter, Saturn, Uranus, and Neptune), the satellites in the outer solar system, comets, and even--through microwave and infrared spectroscopy--the cold dilute gas and grains between the stars, we find a rich organic chemistry, presumably abiological, not only in most of the solar system but throughout the Milky Way galaxy. In part because the composition and surface pressure of the Earth's atmosphere 4 x 10(9) years ago are unknown, laboratory experiments on prebiological organic chemistry are at best suggestive; but we can test our understanding by looking more closely at the observed extraterrestrial organic chemistry. The present Account is restricted to atmospheric organic chemistry, primarily on the large moon of Saturn. Titan is a test of our understanding of the organic chemistry of planetary atmospheres. Its atmospheric bulk composition (N2/CH4) is intermediate between the highly reducing (H2/He/CH4/NH3/H2O) atmospheres of the Jovian planets and the more oxidized (N2/CO2/H2O) atmospheres of the terrestrial planets Mars and Venus. It has long been recognized that Titan's organic chemistry may have some relevance to the events that led to the origin of life on Earth. But with Titan surface temperatures approximately equal to 94 K and pressures approximately equal to 1.6 bar, the oceans of the early Earth have no ready analogue on Titan. Nevertheless, tectonic events in the water ice-rich interior or impact melting and slow re-freezing may lead to an episodic availability of liquid water. Indeed, the latter process is the equivalent of a approximately 10(3)-year-duration shallow aqueous sea over the entire surface of Titan.