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Andrew J. Westphal Christopher Snead Janet Borg Eric Quirico Pierre‐Ivan Raynal Michael E. Zolensky Gianluca Ferrini Luigi Colangeli Pasquale Palumbo 《Meteoritics & planetary science》2002,37(6):855-865
Abstract— It has now been about a decade since the first demonstrations that hypervelocity particles could be captured, partially intact, in aerogel collectors. But the initial promise of a bonanza of partially‐intact extraterrestrial particles, collected in space, has yet to materialize. One of the difficulties that investigators have encountered is that the location, extraction, handling and analysis of very small (10 μm and less) grains, which constitute the vast majority of the captured particles, is challenging and burdensome. Furthermore, current extraction techniques tend to be destructive over large areas of the collectors. Here we describe our efforts to alleviate some of these difficulties. We have learned how to rapidly and efficiently locate captured particles in aerogel collectors, using an automated microscopic scanning system originally developed for experimental nuclear astrophysics. We have learned how to precisely excavate small access tunnels and trenches using an automated micromanipulator and glass microneedles as tools. These excavations are only destructive to the collector in a very small area—this feature may be particularly important for excavations in the precious Stardust collectors. Using actuatable silicon microtweezers, we have learned how to extract and store “naked” particles—essentially free of aerogel—as small as 3 μm in size. We have also developed a technique for extracting particles, along with their terminal tracks, still embedded in small cubical aerogel blocks. We have developed a novel method for storing very small particles in etched nuclear tracks. We have applied these techniques to the extraction and storage of grains captured in aerogel collectors (Particle Impact Experiment, Orbital Debris Collector Experiment, Comet‐99) in low Earth orbit. 相似文献
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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
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V. Orofino L. Colangeli E. Bussoletti F. Strafella 《Astrophysics and Space Science》1987,138(1):127-140
In this paper we present the results of a simplified model to determine the flux emerging from dust envelopes around cool stars. The model proposed holds under the hypotheses of negligible scattering effects and spherical geometry of the dust cloud.The aim of this work is to compare the effects of a graphitic or amorphous composition of the carbon grains in the envelopes. To do this we have used, for the first time, experimental extinction data obtained in the laboratory for submicron amorphous carbon particles.The model has been used to fit the FIR spectral trend of 78 optically thin sources and to reproduce the full spectra of two of the most IR luminous optically-thick sources: CIT 6 and IRC+10216.Our calculations indicate clearly that solid carbon particles around these sources may be amorphous rather than crystalline. 相似文献
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L. Colangeli J.J. Lopez-Moreno P. Nørnberg V. Della Corte F. Esposito E. Mazzotta Epifani J. Merrison C. Molfese P. Palumbo J.F. Rodriguez-Gomez A. Rotundi G. Visconti J.C. Zarnecki 《Planetary and Space Science》2009,57(8-9):1043-1049
Dust and water vapour are fundamental components of the Martian atmosphere. In view of tracing the past environmental conditions on Mars, that possibly favoured the appearing of life forms, it is important to study the present climate and its evolution. Here dust and water vapour have (and have had) strong influence. Of major scientific interest is the quantity and physical, chemical and electrical properties of dust and the abundance of water vapour dispersed in the atmosphere and their exchange with the surface. Moreover, in view of the exploration of the planet with automated systems and in the future by manned missions, it is of primary importance to analyse the hazards linked to these environmental factors. The Martian Environmental Dust Systematic Analyser (MEDUSA) experiment, included in the scientific payload of the ESA ExoMars mission, accommodates a complement of sensors, based on optical detection and cumulative mass deposition, that aims to study dust and water vapour in the lower Martian atmosphere. The goals are to study, for the first time, in-situ and quantitatively, physical properties of the airborne dust, including the cumulative dust mass flux, the dust deposition rate, the physical and electrification properties, the size distribution of sampled particles and the atmospheric water vapour abundance versus time. 相似文献
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Ralf Srama Thomas Stephan Eberhard Grün Norbert Pailer Anton Kearsley Amara Graps Rene Laufer Pascale Ehrenfreund Nicolas Altobelli Kathrin Altwegg Siegfried Auer Jack Baggaley Mark J. Burchell James Carpenter Luigi Colangeli Francesca Esposito Simon F. Green Hartmut Henkel Mihaly Horanyi Annette Jäckel Sascha Kempf Neil McBride Georg Moragas-Klostermeyer Harald Krüger Pasquale Palumbo Andre Srowig Mario Trieloff Peter Tsou Zoltan Sternovsky Oliver Zeile Hans-Peter Röser 《Experimental Astronomy》2009,23(1):303-328
The scientific community has expressed strong interest to re-fly Stardust-like missions with improved instrumentation. We
propose a new mission concept, SARIM, that collects interstellar and interplanetary dust particles and returns them to Earth.
SARIM is optimised for the collection and discrimination of interstellar dust grains. Improved active dust collectors on-board
allow us to perform in-situ determination of individual dust impacts and their impact location. This will provide important
constraints for subsequent laboratory analysis.
The SARIM spacecraft will be placed at the L2 libration point of the Sun–Earth system, outside the Earth’s debris belts and
inside the solar-wind charging environment. SARIM is three-axes stabilised and collects interstellar grains between July and
October when the relative encounter speeds with interstellar dust grains are lowest (4 to 20 km/s). During a 3-year dust collection
period several hundred interstellar and several thousand interplanetary grains will be collected by a total sensitive area
of 1 m2. At the end of the collection phase seven collector modules are stored and sealed in a MIRKA-type sample return capsule.
SARIM will return the capsule containing the stardust to Earth to allow for an extraction and investigation of interstellar
samples by latest laboratory technologies. 相似文献
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Eberhard Grün Ralf Srama Nicolas Altobelli Kathrin Altwegg James Carpenter Luigi Colangeli Karl-Heinz Glassmeier Stefan Helfert Hartmut Henkel Mihaly Horanyi Annette Jäckel Sascha Kempf Markus Landgraf Neil McBride Georg Moragas-Klostermeyer Pasquale Palumbo Han Scholten Andre Srowig Zoltan Sternovsky Xavier Vo 《Experimental Astronomy》2009,23(3):981-999
The DuneXpress observatory will characterize interstellar and interplanetary dust in-situ, in order to provide crucial information
not achievable with remote sensing astronomical methods. Galactic interstellar dust constitutes the solid phase of matter
from which stars and planetary systems form. Interplanetary dust, from comets and asteroids, represents remnant material from
bodies at different stages of early solar system evolution. Thus, studies of interstellar and interplanetary dust with DuneXpress
in Earth orbit will provide a comparison between the composition of the interstellar medium and primitive planetary objects.
Hence DuneXpress will provide insights into the physical conditions during planetary system formation. This comparison of
interstellar and interplanetary dust addresses directly themes of highest priority in astrophysics and solar system science,
which are described in ESA’s Cosmic Vision. The discoveries of interstellar dust in the outer and inner solar system during
the last decade suggest an innovative approach to the characterization of cosmic dust. DuneXpress establishes the next logical
step beyond NASA’s Stardust mission, with four major advancements in cosmic dust research: (1) analysis of the elemental and
isotopic composition of individual interstellar grains passing through the solar system, (2) determination of the size distribution
of interstellar dust at 1 AU from 10 − 14 to 10 − 9 g, (3) characterization of the interstellar dust flow through the planetary system, (4) establish the interrelation of interplanetary
dust with comets and asteroids. Additionally, in supporting the dust science objectives, DuneXpress will characterize dust
charging in the solar wind and in the Earth’s magnetotail. The science payload consists of two dust telescopes of a total
of 0.1 m2 sensitive area, three dust cameras totaling 0.4 m2 sensitive area, and a nano-dust detector. The dust telescopes measure high-resolution mass spectra of both positive and negative
ions released upon impact of dust particles. The dust cameras employ different detection methods and are optimized for (1)
large area impact detection and trajectory analysis of submicron sized and larger dust grains, (2) the determination of physical
properties, such as flux, mass, speed, and electrical charge. A nano-dust detector searches for nanometer-sized dust particles
in interplanetary space. A plasma monitor supports the dust charge measurements, thereby, providing additional information
on the dust particles. About 1,000 grains are expected to be recorded by this payload every year, with 20% of these grains
providing elemental composition. During the mission submicron to micron-sized interstellar grains are expected to be recorded
in statistically significant numbers. DuneXpress will open a new window to dusty universe that will provide unprecedented
information on cosmic dust and on the objects from which it is derived. 相似文献
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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
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V. Formisano F. Angrilli S. Atreya D. Biondi M.I. Blecka L. Colangeli F. Esposito M. Giuranna V. Gnedykh G. Hansen I. Khatuntsev N. Ignatiev A. Jurewicz J. Lopez Moreno A. Mattana E. Mencarelli V. Moroz F. Nespoli R. Orfei V. Orofino D. Patsaev M. Rataj J. Rodriguez B. Saggin L. Zasova 《Planetary and Space Science》2005,53(10):963-974
The Planetary Fourier Spectrometer (PFS) for the Mars Express mission is an infrared spectrometer optimised for atmospheric studies. This instrument has a short wave (SW) channel that covers the spectral range from 1700 to (1.2-) and a long-wave (LW) channel that covers 250- (5.5-). Both channels have a uniform spectral resolution of . The instrument field of view FOV is about 1.6° (FWHM) for the Short Wavelength channel (SW) and 2.8° (FWHM) for the Long Wavelength channel (LW) which corresponds to a spatial resolution of 7 and 12 km when Mars is observed from an height of 250 km. PFS can provide unique data necessary to improve our knowledge not only of the atmosphere properties but also about mineralogical composition of the surface and the surface-atmosphere interaction.The SW channel uses a PbSe detector cooled to 200-220 K while the LW channel is based on a pyroelectric (LiTaO3) detector working at room temperature. The intensity of the interferogram is measured every 150 nm of physical mirrors displacement, corresponding to 600 nm optical path difference, by using a laser diode monochromatic light interferogram (a sine wave), whose zero crossings control the double pendulum motion. PFS works primarily around the pericentre of the orbit, only occasionally observing Mars from large distances. Each measurements take 4 s, with a repetition time of 8.5 s. By working roughly 0.6 h around pericentre, a total of 330 measurements per orbit will be acquired 270 looking at Mars and 60 for calibrations. PFS is able to take measurements at all local times, facilitating the retrieval of surface temperatures and atmospheric vertical temperature profiles on both the day and the night side. 相似文献
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