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A. Rotundi F. J. M. Rietmeijer M. Ferrari V. Della Corte G. A. Baratta R. Brunetto E. Dartois Z. Djouadi S. Merouane J. Borg J. R. Brucato L. Le Sergeant d'Hendecourt V. Mennella M. E. Palumbo P. Palumbo 《Meteoritics & planetary science》2014,49(4):550-575
We present the analyses results of two bulk Terminal Particles, C2112,7,171,0,0 and C2112,9,171,0,0, derived from the Jupiter‐family comet 81P/Wild 2 returned by the Stardust mission. Each particle embedded in a slab of silica aerogel was pressed in a diamond cell. This preparation, as expected, made it difficult to identify the minerals and organic materials present in these particles. This problem was overcome using a combination of three different analytical techniques, viz. FE‐SEM/EDS, IR, and Raman microspectroscopy that allowed identifying the minerals and small amounts of amorphous carbon present in both particles. TP2 and TP3 were dominated by Ca‐free and low‐Ca, Mg‐rich, Mg,Fe‐olivine. The presence of melilite in both particles is supported by IR microspectroscopy, but is not confirmed by Raman microspectroscopy, possibly because the amounts are too small to be detected. TP2 and TP3 show similar silicate mineral compositions, but Ni‐free and low‐Ni, subsulfur (Fe,Ni)S grains are present in TP2 only. TP2 contains indigenous amorphous carbon hot spots; no indigenous carbon was identified in TP3. These nonchondritic particles probably originated in a differentiated body. This work found an unanticipated carbon contamination following the FE‐SEM/EDS analyses. It is suggested that organic materials in the embedding silica aerogel are irradiated during FE‐SEM/EDS analyses creating a carbon gas that develops a strong fluorescence continuum. The combination of the selected analytical techniques can be used to characterize bulk Wild 2 particles without the need of extraction and removal of the encapsulating aerogel. This approach offers a relatively fast sample preparation procedure, but compressing the samples can cause spurious artifacts, viz. silica contamination. Because of the combination of techniques, we account for these artifacts. 相似文献
2.
MarcoPolo-R near earth asteroid sample return mission 总被引：3，自引：0，他引：3
Maria Antonietta Barucci A. F. Cheng P. Michel L. A. M. Benner R. P. Binzel P. A. Bland H. B?hnhardt J. R. Brucato A. Campo Bagatin P. Cerroni E. Dotto A. Fitzsimmons I. A. Franchi S. F. Green L.-M. Lara J. Licandro B. Marty K. Muinonen A. Nathues J. Oberst A. S. Rivkin F. Robert R. Saladino J. M. Trigo-Rodriguez S. Ulamec M. Zolensky 《Experimental Astronomy》2012,33(2-3):645-684
MarcoPolo-R is a sample return mission to a primitive Near-Earth Asteroid (NEA) proposed in collaboration with NASA. It will rendezvous with a primitive NEA, scientifically characterize it at multiple scales, and return a unique sample to Earth unaltered by the atmospheric entry process or terrestrial weathering. MarcoPolo-R will return bulk samples (up to 2?kg) from an organic-rich binary asteroid to Earth for laboratory analyses, allowing us to: explore the origin of planetary materials and initial stages of habitable planet formation; identify and characterize the organics and volatiles in a primitive asteroid; understand the unique geomorphology, dynamics and evolution of a binary NEA. This project is based on the previous Marco Polo mission study, which was selected for the Assessment Phase of the first round of Cosmic Vision. Its scientific rationale was highly ranked by ESA committees and it was not selected only because the estimated cost was higher than the allotted amount for an M class mission. The cost of MarcoPolo-R will be reduced to within the ESA medium mission budget by collaboration with APL (John Hopkins University) and JPL in the NASA program for coordination with ESA’s Cosmic Vision Call. The baseline target is a binary asteroid (175706) 1996 FG3, which offers a very efficient operational and technical mission profile. A binary target also provides enhanced science return. The choice of this target will allow new investigations to be performed more easily than at a single object, and also enables investigations of the fascinating geology and geophysics of asteroids that are impossible at a single object. Several launch windows have been identified in the time-span 2020–2024. A number of other possible primitive single targets of high scientific interest have been identified covering a wide range of possible launch dates. The baseline mission scenario of MarcoPolo-R to 1996 FG3 is as follows: a single primary spacecraft provided by ESA, carrying the Earth Re-entry Capsule, sample acquisition and transfer system provided by NASA, will be launched by a Soyuz-Fregat rocket from Kourou into GTO and using two space segment stages. Two similar missions with two launch windows, in 2021 and 2022 and for both sample return in 2029 (with mission duration of 7 and 8?years), have been defined. Earlier or later launches, in 2020 or 2024, also offer good opportunities. All manoeuvres are carried out by a chemical propulsion system. MarcoPolo-R takes advantage of three industrial studies completed as part of the previous Marco Polo mission (see ESA/SRE (2009)3, Marco Polo Yellow Book) and of the expertise of the consortium led by Dr. A.F. Cheng (PI of the NASA NEAR Shoemaker mission) of the JHU-APL, including JPL, NASA ARC, NASA LaRC, and MIT. 相似文献
3.
Brucato John Robert Strazzulla Giovanni Baratta Giuseppe Mennella Vito Colangeli Luigi 《Earth, Moon, and Planets》2003,92(1-4):307-314
Silicates are one of the principal components present in Solar System objects.Silicates evolve in space modifying their physical properties according to theastronomical environments they go through. To characterise the nature of TNOsin the framework of the formation and evolution of the Solar System, experimentson structural transitions of silicates have been performed in the laboratoryto simulate some of the processing suffered by the dust. The infrared spectralproperties of possible silicate candidates thought to be present in TNOs have beenstudied. The results of thermal annealing of amorphous silicates and amorphisationof crystalline forsterite (pure-Mg olivine) by ion irradiation are presented. Theobservable properties of TNOs surfaces are inferred. 相似文献
4.
Hannah H. Kaplan Victoria E. Hamilton Ellen S. Howell F. Scott Anderson M. Antonella Barrucci John Brucato Thomas H. Burbine Beth E. Clark Ed A. Cloutis Harold C. Connolly Elisabetta Dotto Joshua P. Emery Sonia Fornasier Cateline Lantz Lucy F. Lim Frederic Merlin Alice Praet Dennis C. Reuter Scott A. Sandford Amy A. Simon Driss Takir Dante S. Lauretta 《Meteoritics & planetary science》2020,55(4):744-765
The primary objective of the Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer (OSIRIS‐REx) mission is to return to Earth a pristine sample of carbonaceous material from the primitive asteroid (101955) Bennu. To support compositional mapping of Bennu as part of sample site selection and characterization, we tested 95 spectral indices on visible to near infrared laboratory reflectance data from minerals and carbonaceous meteorites. Our aim was to determine which indices reliably identify spectral features of interest. Most spectral indices had high positive detection rates when applied to spectra of pure, single‐component materials. The meteorite spectra have fewer and weaker absorption features and, as a result, fewer detections with the spectral indices. Indices targeting absorptions at 0.7 and 2.7–3 μm, which are attributable to hydrated minerals, were most successful for the meteorites. Based on these results, we identified a set of 17 indices that are most likely to be useful at Bennu. These indices detect olivines, pyroxenes, carbonates, water/OH‐bearing minerals, serpentines, ferric minerals, and organics. Particle size and albedo are known to affect band depth but had a negligible impact on interpretive success with spectral indices. Preliminary analysis of the disk‐integrated Bennu spectrum with these indices is consistent with expectations given the observed absorption near 3 μm. Our study prioritizes spectral indices to be used for OSIRIS‐REx spectral analysis and mapping and informs the reliability of all index‐derived data products, including a science value map for sample site selection. 相似文献
5.
We are entering in a new era of space exploration signed by sample return missions. Since the Apollo and Luna Program, the study of extraterrestrial samples in laboratory is gathering an increased interest of the scientific community so that nowadays exploration program of the Solar System is characterized by swelling sample return missions. Beside lunar samples, the NASA Stardust mission was the first successful space mission that on 15 January 2006 brought to Earth solid extraterrestrial samples collected from comet 81P/Wild 2 coma. Grains were collected during cometary fly-by into aerogel and once on Earth have been extracted for laboratory analyses. In the coming two decades many space missions on going or under study will harvest samples from minor bodies. Measurements required for detailed analysis that cannot be performed from a robotic spacecraft, will be carried out on Earth laboratories with the highest analytical accuracy attainable so far. An intriguing objective for the next sample return missions is to understand the nature of organic compounds. Organic compounds found in Stardust grains even if processed to large extend during aerogel capturing are here reported. Major objectives of Marco Polo mission are reported. Various ground-based observational programs within the framework of general characterizations of families and classes, cometary–asteroid transition objects and NEOs with cometary albedo are discussed and linked to sample return mission. 相似文献
6.
L. Colangeli Th. Henning J.R. Brucato D. Clément D. Fabian O. Guillois F. Huisken C. Jäger E.K. Jessberger A. Jones G. Ledoux G. Manicó V. Mennella F.J. Molster H. Mutschke V. Pirronello C. Reynaud J. Roser G. Vidali L.B.F.M. Waters 《Astronomy and Astrophysics Review》2003,11(2-3):97-152
Abstract. Silicate grains in space have attracted recently a wide interest of astrophysicists due to the increasing amount and quality
of observational data, especially thanks to the results obtained by the Infrared Space Observatory. The observations have
shown that the presence of silicates is ubiquitous in space and that their properties vary with environmental characteristics.
Silicates, together with carbon, are the principal components of solid matter in space. Since their formation, silicate grains
cross many environments characterised by different physical and chemical conditions which can induce changes to their nature.
Moreover, the transformations experienced in the interplay of silicate grains and the medium where they are dipped, are part
of a series of processes which are the subject of possible changes in the nature of the space environment itself. Then, chemical
and physical changes of silicate grains during their life play a key role in the chemical evolution of the entire Galaxy.
The knowledge of silicate properties related to the conditions where they are found in space is strictly related to the study
in the laboratory of the possible formation and transformation mechanisms they experience. The application of production and
processing methods, capable to reproduce actual space conditions, together with the use of analytical techniques to investigate
the nature of the material samples, form a subject of a complex laboratory experimental approach directed to the understanding
of cosmic matter. The goal of the present paper is to review the experimental methods applied in various laboratories to the
simulation and characterisation of cosmic silicate analogues. The paper describes also laboratory studies of the chemical
reactions undergone and induced by silicate grains. The comparison of available laboratory results with observational data
shows the essential constraints imposed by astronomical observations and, at the same time, indicates the most puzzling problems
that deserve particular attention for the future. The outstanding open problems are reported and discussed. The final purpose
of this paper is to provide an overview of the present stage of knowledge about silicates in space and to provide to the reader
some indication of the future developments in the field.
Received 25 April 2002 / Published online 14 November 2002
Send offprint requests to: L. Colangeli e–mail: colangeli@na.astro.it 相似文献
7.
MARCO POLO: near earth object sample return mission 总被引：1，自引：0，他引：1
M. A. Barucci M. Yoshikawa P. Michel J. Kawagushi H. Yano J. R. Brucato I. A. Franchi E. Dotto M. Fulchignoni S. Ulamec 《Experimental Astronomy》2009,23(3):785-808
MARCO POLO is a joint European–Japanese sample return mission to a Near-Earth Object. This Euro-Asian mission will go to a
primitive Near-Earth Object (NEO), which we anticipate will contain primitive materials without any known meteorite analogue,
scientifically characterize it at multiple scales, and bring samples back to Earth for detailed scientific investigation.
Small bodies, as primitive leftover building blocks of the Solar System formation process, offer important clues to the chemical
mixture from which the planets formed some 4.6 billion years ago. Current exobiological scenarios for the origin of Life invoke
an exogenous delivery of organic matter to the early Earth: it has been proposed that primitive bodies could have brought
these complex organic molecules capable of triggering the pre-biotic synthesis of biochemical compounds. Moreover, collisions
of NEOs with the Earth pose a finite hazard to life. For all these reasons, the exploration of such objects is particularly
interesting and urgent. The scientific objectives of MARCO POLO will therefore contribute to a better understanding of the
origin and evolution of the Solar System, the Earth, and possibly Life itself. Moreover, MARCO POLO provides important information
on the volatile-rich (e.g. water) nature of primitive NEOs, which may be particularly important for future space resource
utilization as well as providing critical information for the security of Earth. MARCO POLO is a proposal offering several
options, leading to great flexibility in the actual implementation. The baseline mission scenario is based on a launch with
a Soyuz-type launcher and consists of a Mother Spacecraft (MSC) carrying a possible Lander named SIFNOS, small hoppers, sampling
devices, a re-entry capsule and scientific payloads. The MSC leaves Earth orbit, cruises toward the target with ion engines,
rendezvous with the target, conducts a global characterization of the target to select a sampling site, and delivers small
hoppers (MINERVA type, JAXA) and SIFNOS. The latter, if added, will perform a soft landing, anchor to the target surface,
and make various in situ measurements of surface/subsurface materials near the sampling site. Two surface samples will be collected by the MSC using
“touch and go” manoeuvres. Two complementary sample collection devices will be used in this phase: one developed by ESA and
another provided by JAXA, mounted on a retractable extension arm. After the completion of the sampling and ascent of the MSC,
the arm will be retracted to transfer the sample containers into the MSC. The MSC will then make its journey back to Earth
and release the re-entry capsule into the Earth’s atmosphere. 相似文献
8.
Since their formation in the outflows of evolved stars, materials suffer in space deep chemical and physical modifications. Most abundant elements (C, N, O, Mg, Si, S and Fe) are present in dust as refractory chemical species. Among them silicates are one of the main constituents. Spectroscopic observations in various astronomical environments have shown that magnesium rich silicates are present both in amorphous and in crystalline form. An accurate interpretation of these observations requires studies on the formation of silicate dust in the atmospheres of giant stars and their evolution in the interstellar medium until their inclusion in protoplanetary disks.Many theoretical works have described the chemical and physical evolution of solids in space and their link to observable optical properties. Laboratory studies of cosmic dust analogues are needed to investigate these processes experimentally.In this work, experiments aimed at simulating the formation of silicates in space are presented. In particular, the laser ablation technique is used to produce amorphous silicates with various Si-Mg-Fe content. The analysis of their thermal evolution is presented. 相似文献
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