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Technology Development and Advanced Planning for Curation of Returned Mars Samples

NASA Johnson Space Center (JSC) curates extraterrestrial samples, providing the international science community with lunar rock and soil returned by the Apollo astronauts, meteorites collected in Antarctica, cosmic dust collected in the stratosphere, and hardware exposed to the space environment. Curation comprises initial characterization of new samples, preparation and allocation of samples for research, and clean, secure long-term storage. The foundations of this effort are the specialized cleanrooms (class 10 to 10,000) for each of the four types of materials, the supporting facilities, and the people, many of whom have been doing detailed work in clean environments for decades. JSC is also preparing to curate the next generation of extraterrestrial samples. These include samples collected from the solar wind, a comet, and an asteroid. Early planning and R\&D are underway to support post-mission sample handling and curation of samples returned from Mars. One of the strong scientific reasons for returning samples from Mars is to search for evidence of current or past life in the samples. Because of the remote possibility that the samples may contain life forms that are hazardous to the terrestrial biosphere, the National Research Council has recommended that all samples returned from Mars be kept under strict biological containment until tests show that they can safely be released to other laboratories. It is possible that Mars samples may contain only scarce or subtle traces of life or prebiotic chemistry that could readily be overwhelmed by terrestrial contamination . Thus, the facilities used to contain, process, and analyze samples from Mars must have a combination of high-level biocontainment and organic / inorganic chemical cleanliness that is unprecedented. JSC has been conducting feasibility studies and developing designs for a sample receiving facility that would offer biocontainment at least the equivalent of current maximum containment BSL-4 (BioSafety Level 4) laboratories, while simultaneously maintaining cleanliness levels equaling those of state-of-the-art cleanrooms. Unique requirements for the processing of Mars samples have inspired a program to develop handling techniques that are much more precise and reliable than the approach (currently used for lunar samples) of employing gloved human hands in nitrogen-filled gloveboxes. Individual samples from Mars are expected to be much smaller than lunar samples, the total mass of samples returned by each mission being 0.5- 1 kg, compared with many tens of kg of lunar samples returned by each of the six Apollo missions. Smaller samples require much more of the processing to be done under microscopic observation. In addition, the requirements for cleanliness and high-level containment would be difficult to satisfy while using traditional gloveboxes. JSC has constructed a laboratory to test concepts and technologies important to future sample curation. The Advanced Curation Laboratory includes a new-generation glovebox equipped with a robotic arm to evaluate the usability of robotic and teleoperated systems to perform curatorial tasks. The laboratory also contains equipment for precision cleaning and the measurement of trace organic contamination.

Lindstrom, David J.↗

Impact of lunar and planetary missions on the space station

The impacts upon the growth space station of several advanced planetary missions and a populated lunar base are examined. Planetary missions examined include sample returns from Mars, the Comet Kopff, the main belt asteroid Ceres, a Mercury orbiter, and a saturn orbiter with multiple Titan probes. A manned lunar base build-up scenario is defined, encompassing preliminary lunar surveys, ten years of construction, and establishment of a permanent 18 person facility with the capability to produce oxygen propellant. The spacecraft mass departing from the space station, mission Delta V requirements, and scheduled departure date for each payload outbound from low Earth orbit are determined for both the planetary missions and for the lunar base build-up. Large aerobraked orbital transfer vehicles (OTV's) are used. Two 42 metric ton propellant capacity OTV's are required for each the the 68 lunar sorties of the base build-up scenario. The two most difficult planetary missions (Kopff and Ceres) also require two of these OTV's. An expendable lunar lander and ascent stage and a reusable lunar lander which uses lunar produced oxygen are sized to deliver 18 metric tons to the lunar surface. For the lunar base, the Space Station must hangar at least two non-pressurized OTV's, store 100 metric tons of cryogens, and support an average of 14 OTV launch, return, and refurbishment cycles per year. Planetary sample return missions require a dedicated quarantine module.

Source record↗

Stardust in STARDUST - the C, N, and O Isotopic Compositions of Wild 2 Cometary Matter in Al foil Impacts

In January 2006, the STARDUST mission successfully returned dust samples from the tail of comet 81P/Wild 2 in two principal collection media, low density silica aerogel and Al foil. While hypervelocity impacts at 6.1 km/s, the encounter velocity of STARDUST, into Al foils are generally highly disruptive for natural, silicate-dominated impactors, previous studies have shown that many craters retain sufficient residue to allow a determination of the elemental and isotopic compositions of the original projectile. We have used the NanoSIMS to perform C, N, and O isotope imaging measurements on four large (59-370 microns diameter) and on 47 small (0.32-1.9 microns diameter) Al foil impact craters as part of the STARDUST Preliminary Examination. Most analyzed residues in and around these craters are isotopically normal (solar) in their C, N, and O isotopic compositions. However, the debris in one large crater shows an average 15N enrichment of approx. 450 %, which is similar to the bulk composition of some isotopically primitive interplanetary dust particles. A 250 nm grain in another large crater has an O-17 enrichment with approx. 2.65 times the solar O-17/O-16 ratio. Such an O isotopic composition is typical for circumstellar oxide or silicate grains from red giant or asymptotic giant branch stars. The discovery of this circumstellar grain clearly establishes that there is authentic stardust in the cometary samples returned by the STARDUST mission. However, the low apparent abundance of circumstellar grains in Wild 2 samples and the preponderance of isotopically normal material indicates that the cometary matter is a diverse assemblage of presolar and solar system materials.

Stadermann, Frank J.↗

Stardust in STARDUST - the C, N, and O Isotopic Compositions of Wild 2 Cometary Matter in Al Foil Impacts

In January 2006, the Stardust mission successfully returned dust samples from the tail of comet 81P/Wild 2 in two principal collection media, low density silica aerogel and Al foil. While hypervelocity impacts at the Stardust encounter velocity of 6.1 kilometers per second into Al foils are generally highly disruptive for natural, silicate-dominated impactors, previous studies have shown that many craters retain sufficient residue to allow a determination of the elemental and isotopic compositions of the original projectile. We have used two NanoSIMS ion microprobes to perform C, N, and O isotope imaging measurements on four large (59-295 micrometer diameter) and on 47 small (0.32-1.9 micrometer diameter) Al foil impact craters as part of the Stardust Preliminary Examination. Most analyzed residues in and around these craters are isotopically normal (solar) in their C, N, and O isotopic compositions. However, the debris in one large crater shows an average N-15 enrichment of approx. 450%o, which is similar to the bulk composition of some isotopically primitive interplanetary dust particles and to components of some primitive meteorites. A 250 nm grain in another large crater has an O-17 enrichment with approx. 2.65 times the solar O-17/O-16 ratio. Such an O isotopic composition is typical for circumstellar oxide or silicate grains from red giant or asymptotic giant branch stars. The discovery of this circumstellar grain clearly establishes that there is authentic stardust in the cometary samples returned by the Stardust mission. However, the low apparent abundance of circumstellar grains in Wild 2 samples and the preponderance of isotopically normal material indicates that the cometary matter is a diverse assemblage of presolar and solar system materials.

Stadermann, Frank J.↗

The Nature of Extraterrestrial Amino Acids in Carbonaceous Chondrites and Links to Their Parent Bodies

Meteorites and samples returned from asteroids and comets provide an important record of the physical and chemical processes that occurred in the early solar system and represent some of the oldest solid materials currently available for laboratory analyses. The delivery of organic matter by extraterrestrial material to the early Earth could have been an important source of complex prebiotic organic molecules available for the emergence of life. Analyses of primitive carbonaceous chondrites over the last five decades have revealed a major insoluble organic component [1,2], as well as a complex and highly diverse suite of soluble organic molecules of prebiotic importance [3,4] that includes carboxylic acids, N-heterocycles, sugars, amino acids, amines, and many other organic molecules that have not yet been identified [5]. Amino acids continue to be a primary focus of many soluble organic analyses in carbonaceous chondrites because (1) these molecules are essential components of life (as the monomers of proteins), (2) they have structural diversity (multiple possible isomers) that can be used to help constrain formation mechanisms and parent body conditions, and (3) most amino acids identified in carbonaceous chondrites are chiral, a property that can be used to distinguish between amino acids of extraterrestrial and terrestrial origins. The degree of parent body hydrothermal alteration has been shown to have a major influence on the formation and destruction of amino acids in carbonaceous meteorites as observed in the measured abundances and molecular distributions [6]. Aqueous alteration in primitive asteroids could have also led to the preferential enrichment of some left-handed amino acids over their right-handed forms, an astounding discovery that suggests that the origin of life on Earth or elsewhere was biased toward left-handed amino acid homochirality [7,8]. This talk will give an overview of what is known about the amino acid composition of carbonaceous chondrites, present some key unanswered questions, and discuss how the analysis of samples returned from asteroids Ryugu and Bennu will further advance our understanding of parent body chemistry and potential contributions from carbonaceous asteroids to the origin of life on Earth or elsewhere.

Daniel P. Glavin↗

Optimal solar sail spiral to escape

A solar sail is being considered for various solar system missions, such as a comet rendezvous and a planetary sample return. Such missions might include a planetocentric escape or capture trajectory segment. This paper considers a method for calculating time optimal planetocentric solar sail spiral trajectories to near escape and orbit to orbit transfers. A number of examples illustrate trajectories generated with a computer program, SUNSPOT, based on this analysis.

Sackett, L. L.↗

Analysis and interpretation of CCD data on P/Halley and physical parameters and activity status of cometary nuclei at large heliocentric distance

The scientific objectives were as follows: (1) to construct a well sampled photometric time series of comet Halley extending to large heliocentric distances both post and pre-perihelion passage and derive a precise ephemeris for the nuclear spin so that the physical and chemical characteristics of individual regions of activity on the nucleus can be determined; and (2) to extend the techniques in the study of Comet Halley to the study of other cometary nuclei and to obtain new observational data.

Belton, Michael J. S.↗

Technical Tension Between Achieving Particulate and Molecular Organic Environmental Cleanliness: Data from Astromaterial Curation Laboratories

NASA Johnson Space Center operates clean curation facilities for Apollo lunar, Antarctic meteorite, stratospheric cosmic dust, Stardust comet and Genesis solar wind samples. Each of these collections is curated separately due unique requirements. The purpose of this abstract is to highlight the technical tensions between providing particulate cleanliness and molecular cleanliness, illustrated using data from curation laboratories. Strict control of three components are required for curating samples cleanly: a clean environment; clean containers and tools that touch samples; and use of non-shedding materials of cleanable chemistry and smooth surface finish. This abstract focuses on environmental cleanliness and the technical tension between achieving particulate and molecular cleanliness. An environment in which a sample is manipulated or stored can be a room, an enclosed glovebox (or robotic isolation chamber) or an individual sample container.

Allton, J. H.↗

Organic Contamination Baseline Study in NASA Johnson Space Center Astromaterials Curation Laboratories

Future robotic and human spaceflight missions to the Moon, Mars, asteroids, and comets will require curating astromaterial samples with minimal inorganic and organic contamination to preserve the scientific integrity of each sample. 21st century sample return missions will focus on strict protocols for reducing organic contamination that have not been seen since the Apollo manned lunar landing program. To properly curate these materials, the Astromaterials Acquisition and Curation Office under the Astromaterial Research and Exploration Science Directorate at NASA Johnson Space Center houses and protects all extraterrestrial materials brought back to Earth that are controlled by the United States government. During fiscal year 2012, we conducted a year-long project to compile historical documentation and laboratory tests involving organic investigations at these facilities. In addition, we developed a plan to determine the current state of organic cleanliness in curation laboratories housing astromaterials. This was accomplished by focusing on current procedures and protocols for cleaning, sample handling, and storage. While the intention of this report is to give a comprehensive overview of the current state of organic cleanliness in JSC curation laboratories, it also provides a baseline for determining whether our cleaning procedures and sample handling protocols need to be adapted and/or augmented to meet the new requirements for future human spaceflight and robotic sample return missions.

Calaway, Michael J.↗

An Evolutionary System of Mineralogy. Part I: Stellar Mineralogy (>13 to 4.6 Ga)

Minerals preserve records of the physical, chemical, and biological histories of their origins and subsequent alteration, and thus provide a vivid narrative of the evolution of Earth and other worlds through billions of years of cosmic history. Mineral properties, including trace and minor elements, ratios of isotopes, solid and fluid inclusions, external morphologies, and other idiosyncratic attributes, represent information that points to specific modes of formation and subsequent environmental histories—information essential to understanding the co-evolving geosphere and biosphere. This perspective suggests an opportunity to amplify the existing system of mineral classification, by which minerals are defined solely on idealized end-member chemical compositions and crystal structures. Here we present the first in a series of contributions to explore a complementary evolutionary system of mineralogy—a classification scheme that links mineral species to their paragenetic modes. The earliest stage of mineral evolution commenced with the appearance of the first crystals in the universe at >13 Ga and continues today in the expanding, cooling atmospheres of countless evolved stars, which host the high-temperature (T > 1000 K), low-pressure (P < 10-2 atm) condensation of refractory minerals and amorphous phases. Most stardust is thought to originate in three distinct processes in carbon- and/or oxygen-rich mineral-forming stars: (1) condensation in the cooling, expanding atmospheres of asymptotic giant branch stars; (2) during the catastrophic explosions of supernovae, most commonly core collapse (Type II) supernovae; and (3) classical novae explosions, the consequence of runaway fusion reactions at the surface of a binary white dwarf star. Each stellar environment imparts distinctive isotopic and trace element signatures to the micro- and nanoscale stardust grains that are recovered from meteorites and micrometeorites collected on Earth’s surface, by atmospheric sampling, and from asteroids and comets. Although our understanding of the diverse mineral-forming environments of stars is as yet incomplete, we present a preliminary catalog of 41 distinct natural kinds of stellar minerals, representing 22 official International Mineralogical Association (IMA) mineral species, as well as 2 as yet unapproved crystalline phases and 3 kinds of non-crystalline condensed phases not codified by the IMA.

Robert M. Hazen↗

Sampling tool concepts for Enceladus Lander in-situ analysis

A potential future in-situ lander mission to the surface of Enceladus could be the lowest cost mission to determine if life exists beyond Earth since material from the subsurface ocean, where the presence of hydrothermal activity has been strongly suggested by the Cassini mission, is available on its surface after being ejected by plumes and then settling on the surface. In addition, the low radiation environment of Enceladus would not significantly alter the chemical makeup of samples recently deposited on the surface. A study was conducted to explore various sampling devices that could be used by an in-situ lander mission to provide 1cc to 5cc volume samples to instruments. In addition to temperature and vacuum environmental conditions, the low surface gravity of Enceladus (1% of Earth gravity) represents a new challenge for surface sampling that is not met by sampling systems developed for microgravity (e.g., comets and asteroids) or higher gravity (e.g., Europa 13%g, Moon 16%g, or Mars 38%g) environments. It is desired to acquire surface plume material that has accumulated in the top 1cm to ensure acquisition of the least processed material. Several sampling devices were developed or adapted and then tested in simulated conditions that resemble the Enceladus surface properties. These devices and test results are presented in this paper.

Genta, Giancarlo↗

Insight into Primordial Solar System Oxygen Reservoirs from Returned Cometary Samples

The recent successful rendezvous of the Stardust spacecraft with comet Wild-2 will be followed by its return of cometary dust to Earth in January 2006. Results from two separate dust impact detectors suggest that the spacecraft collected approximately the nominal fluence of at least 1,000 particles larger than 15 micrometers in size. While constituting only about one microgram total, these samples will be sufficient to answer many outstanding questions about the nature of cometary materials. More than two decades of laboratory studies of stratospherically collected interplanetary dust particles (IDPs) of similar size have established the necessary microparticle handling and analytical techniques necessary to study them. It is likely that some IDPs are in fact derived from comets, although complex orbital histories of individual particles have made these assignments difficult to prove. Analysis of bona fide cometary samples will be essential for answering some fundamental outstanding questions in cosmochemistry, such as (1) the proportion of interstellar and processed materials that comprise comets and (2) whether the Solar System had a O-16-rich reservoir. Abundant silicate stardust grains have recently been discovered in anhydrous IDPs, in far greater abundances (200 5,500 ppm) than those in meteorites (25 ppm). Insight into the more subtle O isotopic variations among chondrites and refractory phases will require significantly higher precision isotopic measurements on micrometer-sized samples than are currently available.

Brownlee, D. E.↗

STARDUST: An Incredulous Dream to Incredible Return

This viewgraph presentation reviews the Stardust mission. The goal of the mission was to return to Earth a very small part of a comet for study. The success of the mission gave us a small part of a comet to use for research into questions such as the cometary origin of water and life on earth and the formation of the solar system. The slides review the challenges, the strategy, the laboratory experiments, the instrument development, the characteristics of Aerogel, the Stardust trajectory, pictures of the samples and a listing of the firsts that were accomplished during the Stardust project.

STARDUST↗

Numerical simulations of cometary dust

Most observations of comets are done photometrically or spectrophotometrically. The interpretation of the aperture-averaged flux is relatively simple for an isotropic, radially expanding coma of infinite extent - the canonical model. However, the interpretation of the observations is not so clear when the motion of the dust is affected by radiation pressure, or when the emission is time-varying and anisotropic. For example, in a sample of CCD images of 10 comets, Jewitt and Meech (1987, Ap.J. 317, 992) found that the photometric profiles of only three comets were consistent, within the observational errors, with the profiles predicted form the canonical model. Photometric observations with large apertures, however, seem to suggest that the canonical model may be quite adequate (c.f. Osip, Schleicher, and Millis, 1992, Icarus 98, 115). The dust itself is characterized by a size distribution, with size dependencies on the expansion velocity, the scattered and thermal radiation, the response to radiation pressure, and probably the density. How good then are the approximations normally used in determining the production rates of the dust when these effects are present? As part of a program to better understand the dynamics of cometary dust and gas, a computer program has been developed which numerically simulates the emission of both dust and gas from a tilted rotating nucleus.

Lien, David J.↗

Curation of Frozen Samples

NASA's Johnson Space Center (JSC) and the Astromaterials Curator are charged by NPD 7100.10D with the curation of all of NASA s extraterrestrial samples, including those from future missions. This responsibility includes the development of new sample handling and preparation techniques; therefore, the Astromaterials Curator must begin developing procedures to preserve, prepare and ship samples at sub-freezing temperatures in order to enable future sample return missions. Such missions might include the return of future frozen samples from permanently-shadowed lunar craters, the nuclei of comets, the surface of Mars, etc. We are demonstrating the ability to curate samples under cold conditions by designing, installing and testing a cold curation glovebox. This glovebox will allow us to store, document, manipulate and subdivide frozen samples while quantifying and minimizing contamination throughout the curation process.

Fletcher, L. A.↗

The case for planetary sample return missions. I - Origin of the solar system

The scientific aims and proposed scenarios of sample-return missions (SRMs) to Mars, Venus, comets, and asteroids are reviewed. SRMs are currently being evaluated as natural follow-ons to the NASA remote-sensing orbiter missions of the 1990s. The technological advantages of ground laboratory analysis of returned samples are discussed; and it is argued that SRMs to large evolved bodies can provide a record of (1) the composition of the solar system at different heliocentric distances and (2) the nature of the processes that led to the accretion of small objects (preserved as comets and asteroids) into large planetary bodies. Also considered are NASA research and analysis programs needed to support studies of solar-system origin. It is recommended that planning of SRMs be begun immediately, although they may not be feasible before the year 2000.

Drake, Michael J.↗