Search NASA⌕ Search

SEARCH · Search NASA

Results for “Comet Sample”

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 91 records · Page 5

Cryogenic Curation: Isolated Technology and Mission Operational Requirements for Sample Return

Future lunar, Mars, asteroid, and comet sample return missions may collect samples that have been preserved at sub-freezing or even cryogenic temperatures. For such samples, the study of volatiles and temperature-sensitive minerals will have high priority. Valuable geochemical and mineralogical information will be lost if such samples are allowed to reach ambient temperatures on Earth. The ability to store, document, subdivide, and transport extraterrestrial geologic samples while maintaining sub-freezing or cryogenic temperatures, possibly as low as 40 K, is required for the complete scientific study of samples from cold environments.

Calaway, Michael J.↗

Wild2 approach maneuver strategy used for Stardust spacecraft (extended abstract)

Stardust, NASA's first dedicated sample return mission to a comet, successfully flew through the comet dust around Wold2 on January 2, 2004. The spacecraft flew within 236 km of the comet, meeting the mission requirement of 250+/- 50 km on flyby distance. Stardust collected dust particles and took several images of the comet while flying close to Wild2. The spacecraft will return to earth with the comet samples on January 15, 2006. To accomplish the above objective, a large Deep Space Maneuver (DSM#) was implemented during June 17 and 18, 2003 and a series of Trajectory Correction Maneuvers (TCMs) were also implemented during the 30 days prior to encounter. Both maneuver design and executions were influenced by number of factors including the small body ephemeris uncertainty, predictability of small forces arising from 3-axis attitude limit cycling and spacecraft slews. Maneuver design processes, including contingency plans, and maneuver performance characteristics, are discussed in this paper.

dust↗

Recent Developments in the Curation of Cold, Volatile-Rich Extraterrestrial Samples

In recent years, the study of samples from cold, potentially volatile-rich Solar System bodies has increased dramatically. Returned samples from low- or cryogenic-temperature regions are highly sensitive to ambient temperatures, pressures, and materials. In order to maximize the scientific utility of such samples, they must be returned, handled, and stored under conditions that minimize sample alteration and contamination. The Johnson Space Center (JSC) Astromaterials Acquisition and Curation Office (hereafter called the Curation Office) is currently developing the ability to curate cold, volatile-rich samples; this abstract summarizes these efforts for Apollo lunar samples, organic-rich meteorites, comet samples, and lunar polar samples.

Mitchell, J. L.↗

Electric Propulsion System Selection Process for Interplanetary Missions

The disparate design problems of selecting an electric propulsion system, launch vehicle, and flight time all have a significant impact on the cost and robustness of a mission. The effects of these system choices combine into a single optimization of the total mission cost, where the design constraint is a required spacecraft neutral (non-electric propulsion) mass. Cost-optimal systems are designed for a range of mass margins to examine how the optimal design varies with mass growth. The resulting cost-optimal designs are compared with results generated via mass optimization methods. Additional optimizations with continuous system parameters address the impact on mission cost due to discrete sets of launch vehicle, power, and specific impulse. The examined mission set comprises a near-Earth asteroid sample return, multiple main belt asteroid rendezvous, comet rendezvous, comet sample return, and a mission to Saturn.

Landau, Damon↗

The Unique Scientific Value of Returned Samples

Most of the materials in the universe are so distant or inaccessible that the only way we can study them is remotely using various types of telescopes. However, in some cases we can study these materials directly because the samples become physically available to us. Some samples come to us of their own accord in the form of meteorites and cosmic dust. In other cases we have to work hard to carry out sample return missions like Apollo, Stardust, OSIRIS-REx, Hayabusa, and Hayabusa2 in order to get the samples ourselves. Once samples are physically available in terrestrial laboratories, we can learn details about their compositions and histories that could never be established by remote observations. This talk will highlight some of the unique scientific advances that can be made through the study of extraterrestrial materials, and will describe the various ways in which samples become available for study, with a focus on the acquisition of samples by sample return spacecraft missions. Aspects of NASA’s Stardust comet sample return mission and JAXA’s Hayabusa asteroid sample return mission will be highlighted and scientific highlights of these missions will be discussed. Finally, the presentation will end with an overview of the current status of NASA’s OSIRIS-Rex mission, which will is currently at Asteroid (101955) Bennu and will be returning samples to Earth in 2023.

Extraterrestrial Samples↗

Advanced Curation Preparation for Mars Sample Return and Cold Curation

NASA Curation is tasked with the care and distribution of NASA's sample collections, such as the Apollo lunar samples and cometary material collected by the Stardust spacecraft. Curation is also mandated to perform Advanced Curation research and development, which includes improving the curation of existing collections as well as preparing for future sample return missions. Advanced Curation has identified a suite of technologies and techniques that will require attention ahead of Mars sample return (MSR) and missions with cold curation (CCur) requirements, perhaps including comet sample return missions.

Fries, M. D.↗

BiBlade Sampling Tool Validation for Comet Surface Environments

The BiBlade sampling chain was developed for use in a potential Comet Surface Sample Return mission. Following prior versions of the sampling tool, a new tool was developed and validated to TRL 6. Sample acquisition testing was performed across a range of comet simulants and operational conditions. Tool operation was validated in a thermal-vacuum chamber. The end-to-end sampling chain was validated including sampling, sample measurement, and sample transfer. The sampling system is now ready for flight implementation.

Backes, Paul↗

Compositional evidence for chondrule origins of low‐Ca pyroxenes in comet Wild 2 and a giant cluster IDP

Abstract A literature compilation of 1136 low‐Ca pyroxene compositions from chondrules from 12 primitive type 2–3 carbonaceous, ordinary and enstatite chondrite groups define unique regions on an Al 2 O 3 and Cr 2 O 3 diagram when compared to low‐Ca pyroxenes from equilibrated type 4‐6 chondrites. Measured compositions of 100 low‐Ca pyroxenes from comet Wild 2 and a giant cluster IDP of probable cometary origin are similar to each other and fall in the type 2–3 chondrite chondrule region suggesting that most of the pyroxenes likely formed in the solar nebula like conventional chondrules. The data imply that most low Ca‐pyroxenes from comet Wild 2 and the giant cluster IDP formed from igneous crystallization processes and did not experience significant thermal metamorphism, indicating that the low‐Ca pyroxenes were unlikely incorporated into large parent bodies prior to accretion in their respective comet bodies. An intriguing group of nine low‐Ca pyroxenes from comet Wild 2 with low Cr and Al that fall where type 4–6 chondrites are located are interpreted as products of condensation. The compositional data combined with previously measured oxygen isotopes on 17 low‐Ca pyroxenes support earlier conclusions that comet samples have links with carbonaceous, ordinary, and possibly enstatite chondrite groups. Our results provide additional evidence that comets accreted materials from multiple chondrule reservoirs throughout the solar nebula.

Geochemistry & Geophysics↗

Infrared Spectroscopy of Parent Volatiles in Comets: Implications for Astrobiology

Current cometary orbits provide information on their recent dynamical history. However, determining a given comet's formation region from its current dynamical state alone is complicated by radial migration in the proto-planetary disk and by dynamical interactions with the growing giant planets. Because comets reside for long periods of time in the outer Solar System, the ices contained in their nuclei (native ices) retain a relatively well-preserved footprint of when and where they formed, and this in turn can provide clues to conditions in the formation epoch. As a comet approaches the Sun, sublimation of its native ices releases parent volatiles into the coma where they can be measured spectroscopically. The past to - 15 years have seen the advent of infrared spectrometers with high sensitivity between about 2.8 and 5.0 micron, enabling a taxonomy among comets based on abundances of parent volatiles (e.g., H2O, CO, CH4, C2H6, HCN, CH30H, H2CO, NH3). Such molecules are of keen interest to Astrobiology, as they include important pre-biotic species that likely were required for the emergence of life on Earth and perhaps elsewhere. Approximately 20 comets have thus far been characterized, beginning with C/1996 82 (Hyakutake) in 1996. Molecular production rates are established through comparison of observed emission line intensities with those predicted by quantum mechanical fluorescence models. Abundances of parent volatiles (relative to H2O) vary among even the relatively small number of comets sampled, with the most volatile species (CO and CH4) displaying the largest variations. Techniques developed for measuring parent volatile abundances in comets will be discussed, as will possible implications for their formation.

DiSanti, Michael A.↗

ARES Biennial Report 2012 Final

Since the return of the first lunar samples, what is now the Astromaterials Research and Exploration Science (ARES) Directorate has had curatorial responsibility for all NASA-held extraterrestrial materials. Originating during the Apollo Program (1960s), this capability at Johnson Space Center (JSC) included scientists who were responsible for the science planning and training of astronauts for lunar surface activities as well as experts in the analysis and preservation of the precious returned samples. Today, ARES conducts research in basic and applied space and planetary science, and its scientific staff represents a broad diversity of expertise in the physical sciences (physics, chemistry, geology, astronomy), mathematics, and engineering organized into three offices (figure 1): Astromaterials Research (KR), Astromaterials Acquisition and Curation (KT), and Human Exploration Science (KX). Scientists within the Astromaterials Acquisition and Curation Office preserve, protect, document, and distribute samples of the current astromaterials collections. Since the return of the first lunar samples, ARES has been assigned curatorial responsibility for all NASA-held extraterrestrial materials (Apollo lunar samples, Antarctic meteorites - some of which have been confirmed to have originated on the Moon and on Mars - cosmic dust, solar wind samples, comet and interstellar dust particles, and space-exposed hardware). The responsibilities of curation consist not only of the longterm care of the samples, but also the support and planning for future sample collection missions and research and technology to enable new sample types. Curation provides the foundation for research into the samples. The Lunar Sample Facility and other curation clean rooms, the data center, laboratories, and associated instrumentation are unique NASA resources that, together with our staff's fundamental understanding of the entire collection, provide a service to the external research community, which relies on access to the samples. The curation efforts are greatly enhanced by a strong group of planetary scientists who conduct peerreviewed astromaterials research. Astromaterials Research Office scientists conduct peer-reviewed research as Principal or Co-Investigators in planetary science (e. g., cosmochemistry, origins of solar systems, Mars fundamental research, planetary geology and geophysics) and participate as Co-Investigators or Participating Scientists in many of NASA's robotic planetary missions. Since the last report, ARES has achieved several noteworthy milestones, some of which are documented in detail in the sections that follow. Within the Human Exploration Science Office, ARES is a world leader in orbital debris research, modeling and monitoring the debris environment, designing debris shielding, and developing policy to control and mitigate the orbital debris population. ARES has aggressively pursued refinements in knowledge of the debris environment and the hazard it presents to spacecraft. Additionally, the ARES Image Science and Analysis Group has been recognized as world class as a result of the high quality of near-real-time analysis of ascent and on-orbit inspection imagery to identify debris shedding, anomalies, and associated potential damage during Space Shuttle missions. ARES Earth scientists manage and continuously update the database of astronaut photography that is predominantly from Shuttle and ISS missions, but also includes the results of 40 years of human spaceflight. The Crew Earth Observations Web site (http://eol.jsc.nasa.gov/Education/ESS/crew.htm) continues to receive several million hits per month. ARES scientists are also influencing decisions in the development of the next generation of human and robotic spacecraft and missions through laboratory tests on the optical qualities of materials for windows, micrometeoroid/orbital debris shielding technology, and analog activities to assess surface science operations. ARES serves as host to numerous students and visiting scientists as part of the services provided to the research community and conducts a robust education and outreach program. ARES scientists are recognized nationally and internationally by virtue of their success in publishing in peer-reviewed journals and winning competitive research proposals. ARES scientists have won every major award presented by the Meteoritical Society, including the Leonard Medal, the most prestigious award in planetary science and cosmochemistry; the Barringer Medal, recognizing outstanding work in the field of impact cratering; the Nier Prize for outstanding research by a young scientist; and several recipients of the Nininger Meteorite Award. One of our scientists received the Department of Defense (DoD) Joint Meritorious Civilian Service Award (the highest civilian honor given by the DoD). ARES has established numerous partnerships with other NASA Centers, universities, and national laboratories. ARES scientists serve as journal editors, members of advisory panels and review committees, and society officers, and several scientists have been elected as Fellows in their professional societies. This biennial report summarizes a subset of the accomplishments made by each of the ARES offices and highlights participation in ongoing human and robotic missions, development of new missions, and planning for future human and robotic exploration of the solar system beyond low Earth orbit.

Stansbery, Eileen↗

Laboratory Simulations: The Primordial Comet Mantle

Laboratory data are needed to understand the formation of organics in cometary and precometary materials and for deciding on the fate of the volatiles. Appropriate experiments were described in the talk at Milipitas. Because of its importance for the comet sample return mission, I discuss here the relevance of this data for predicting the thickness, nature, and ability to survive of the cosmic-ray produced primordial comet mantle ('crust'). That part of the mantle which becomes predominantly refractory is approx. 30 gm/sq cm thick. The tensile strength of this outer mantle is such that it might survive the comet's entrance into the inner solar system. In addition, important modifications to the ices occur to depths approx. 300 gm/cu cm. Based on this it is expected that a deep probe is needed to obtain minimally altered material.

Johnson, R. E.↗

Optimization of multiple target electric propulsion trajectories.

Development of the mathematical basis for the generation of multiple target low-thrust trajectories. The unique trajectory shaping capabilities of electric propulsion make it ideally suited for modifying the path of the spacecraft to effect close encounters of selected asteroids with only slight penalties in performance. Each intermediate encounter with an asteroid involves the optimization of four parameters, the encounter time and the three components of the relative velocity at encounter. A second type of mission amenable to this analysis is that of asteroid or comet sample return missions. For missions of this type, both launch date and division of departure and return flight times are capable of being optimized. Use is made of the traditional calculus of variations to derive the necessary conditions that must be satisfied for both types of missions. In addition, examples are presented of both a Comet Encke rendezvous mission with multiple encounters of the asteroids Aschera and Alekto and also a sample return mission from the asteroid Flora.

Sauer, C. G., Jr.↗

Laboratory analyses of micron-sized solid grains: Experimental techniques and recent results

Morphological and spectrophotometric investigations have been extensively applied in the past years to various kinds of micron and/or submicron-sized grains formed by materials which are candidate to be present in space. The samples are produced in the laboratory and then characterized in their physio-chemical properties. Some of the most recent results obtained on various kinds of carbonaceous materials are reported. Main attention is devoted to spectroscopic results in the VUV and IR wavelength ranges, where many of the analyzed samples show typical fingerprints which can be identified also in astrophysical and cometary materials. The laboratory methodologies used so far are also critically discussed in order to point out capabilities and present limitations, in the view of possible application to returned comet samples. Suggestions are given to develop new techniques which should overcome some of the problems faced in the manipulation and analysis of micron solid samples.

Colangeli, L.↗

Plume Collection Strategies for Icy World Sample Return

Three icy worlds in the solar system display evidence of pluming activity. Water vapor and ice particles emanate from cracks near the south pole of Saturn's moon Enceladus. The plume gas contains simple hydrocarbons that could be fragments of larger, more complex organics. More recently, observations using the Hubble and Herschel space telescopes have hinted at transient water vapor plumes at Jupiter's moon Europa and the dwarf planet Ceres. Plume materials may be ejected directly from possible sub-surface oceans, at least on Enceladus. In such oceans, liquid water, organics, and energy may co-exist, making these environments habitable. The venting of habitable ocean material into space provides a unique opportunity to capture this material during a relatively simple flyby mission and return it to Earth. Plume collection strategies should enable investigations of evidence for life in the returned samples via laboratory analyses of the structure, distribution, isotopic composition, and chirality of the chemical components (including biomolecules) of plume materials. Here, we discuss approaches for the collection of dust and volatiles during flybys through Enceladus' plume, based on Cassini results and lessons learned from the Stardust comet sample return mission. We also highlight areas where sample collector and containment technology development and testing may be needed for future plume sample return missions.

Stardust Collector↗

Advanced solar electric propulsion (ASEP) for planetary missions

This paper defines an advanced SEP concept based upon demonstrated ion thruster technology improvements and projected improvements in solar array technology. The ASEP concept utilizes an 'integrated' rather than a 'stage' approach and assumes 30 cm Hg ion thrusters capable of operation near 7 kWe each. The mission performance using the ASEP system is presented for three missions: (1) Saturn orbiter, (2) comet rendezvous and (3) comet sample return. The ASEP system provides significant mission performance improvements. The simpler, fewer thruster ASEP system design may provide cost as well as performance benefits for the missions examined when compared to ballistic or SEP stage mission options.

Jones, R. M.↗

Intact capture of hypervelocity particles

Knowledge of the phase, structure, and crystallography of cosmic particles, as well as their elemental and isotopic compositions, would be very valuable information toward understanding the nature of our solar system. This information can be obtained from the intact capture of large mineral grains of cosmic particles from hypervelocity impacts. Hypervelocity experiments of intact capture in underdense media have indicated realistic potential in this endeaver. The recovery of the thermal blankets and louvers from the Solar Max spacecraft have independently verified this potential in the unintended capture of cosmic materials from hypervelocity impacts. Passive underdense media will permit relatively simple and inexpensive missions to capture cosmic particles intact, either by going to a planetary body or by waiting for the particles to come to the Shuttle or the Space Station. Experiments to explore the potential of using various underdense media for an intact comet sample capture up to 6.7 km/s were performed at NASA Ames Research Center Vertical Gun Range. Explorative hypervelocity experiments up to 7.9 km/s were also made at the Ernst Mach Institute. These experiments have proven that capturing intact particles at hypervelocity impacts is definitely possible. Further research is being conducted to achieve higher capture ratios at even higher hypervelocities for even smaller projectiles.

Tsou, P.↗

Composition of dust from Comet P/Halley: The mineral fraction

The composition of dust from Comet Halley was investigated in situ during the Vega 1, Vega 2, and Giotto encounters by the PIA/PUMA impact mass spectrometers. More than 5000 meaningful spectra of individual dust particles were obtained, most in a compressed mode. The interpretation of these spectra in terms of elemental and mineralogical composition will be discussed. Accounting for these difficulties, the following conclusions can be derived for the mineral fraction of dust particles: (1) the observed compositions are compatible with the full range of observed meteoritic minerals (in particular mafic silicates, plagioclases, sulfides, oxides); and (2) within each mineralogical class, the spread in composition appears much wider and more uniform than in meteorites. The low overall density and very large excess of light elements will be discussed. These first direct results on cometary dust considerably strengthen the case for a comet sample return mission.

Langevin, Y.↗

Anomalous molecular abundances and the depletion of NH2 in Comet P/Giacobini-Zinner

Observations of the CN, C2, C3, and NH2 molecules in spectra of the Comet P/Giacobini-Zinner (P/G-Z) obtained during the 1985 apparition are presented. Haser-model production rates are derived, and it is found that Q(C2)/Q(CN) and Q(C3)/Q(CN) are low compared to those in normal comets. This indicates that C2 and C3 were underabundance in P/G-Z, in agreement with previous results. Q(NH2)/Q(CN) is determined for five comets for the first time to determine a 'normal' value for this ratio. The ratio for P/G-Z is low compared to the value for the ensemble, suggesting that NH2 was underabundant. For the five-comet sample, Q(C3)/Q(CN) exhibits a strong dependence with heliocentric distance, in contrast to Q(C2)/Q(CN) and Q(C3)/Q(CN). The dust-to-gas ratio is characterized by calculating the product of the dust-grain albedo, the filling factor, and the projected radius of the aperture and by computing the dust-to-gas mass ratio.

Beaver, John E.↗