Proton Induced X-Ray Emission (Pixe) Analysis of Meteoritic Microsamples

AbstractInterplanetary dust particles (IDPs) collected in the stratosphere are thought to be mostly of cometary origin. They survived heating during their deceleration in the earth’s atmosphere (1). Because of their small size (< 50 μm ) and mass (< 10−7 g) they are difficult to analyse. Special preparation and examination methods have been developed for their investigations (2). We set out to study the trace-element-composition of these particles using the Heidelberg proton microprobe.

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On Two Mechanisms of X-Ray Generation in Comets

International Astronomical Union Colloquium ◽

10.1017/s025292110008492x ◽

1985 ◽

Vol 85 ◽

pp. 365-368

Author(s):

S. Ibadov

Keyword(s):

High Temperature ◽

Interplanetary Dust ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

Temperature Plasma ◽

X Ray ◽

Plasma Generation ◽

High Temperature Plasma

AbstractThe intensity of solar X-radiation scattered by a comet is calculated and compared to the proper X-radiation of the comet due to impacts of cometary and interplanetary dust particles. Detection of X-radiation of dusty comets at small heliocentric distances (R ≤ 1 a.u.) is found to be an indicator of high-temperature plasma generation as result of grain collisions.

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The Origin of Organic Matter in the Solar System: Evidence from the Interplanetary Dust Particles

Symposium - International Astronomical Union ◽

10.1017/s0074180900193404 ◽

2004 ◽

Vol 213 ◽

pp. 275-280 ◽

Cited By ~ 1

Author(s):

G. J. Flynn ◽

L. P. Keller ◽

C. Jacobsen ◽

S. Wirick

Keyword(s):

Organic Matter ◽

Gas Phase ◽

Interplanetary Dust ◽

Dust Particles ◽

Aqueous Processing ◽

Interplanetary Dust Particles ◽

Volatile Elements ◽

Edge Structure ◽

X Ray ◽

X Ray Absorption

Interplanetary dust particles (IDPs), ∼ 10μm particles from comets and asteroids, have been collected by NASA from the Earth's stratosphere. We compared carbon X-ray Absorption Near-Edge Structure (XANES) and Fourier Transform Infra-Red (FTIR) spectra of anhydrous and hydrated interplanetary dust particles and found that anhydrous and hydrated IDPs have similar types and abundances of organic carbon. This is different from results on meteorites, which show that hydrated carbonaceous meteorites contain abundant organic matter, while anhydrous carbonaceous meteorites contain less carbon mostly in elemental form. But all anhydrous carbonaceous meteorites are depleted in moderately volatile and volatile elements in a pattern that suggested they experienced temperatures in excess of 1200°C, a temperature sufficient to destroy any organic matter they originally contained, while many anhydrous IDPs show no evidence of severe heating. These IDP results indicate that the bulk of the pre-biotic organic matter in extraterrestrial materials formed before aqueous processing, possibly by irradiation of C-bearing ices or by a Fisher-Tropsch type process operating in the gas phase of the nebula or in the interstellar medium.

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The asteroid-comet continuum from laboratory and space analyses of comet samples and micrometeorites

Proceedings of the International Astronomical Union ◽

10.1017/s1743921316002994 ◽

2015 ◽

Vol 11 (A29A) ◽

pp. 253-256 ◽

Cited By ~ 2

Author(s):

Cécile Engrand ◽

Jean Duprat ◽

Noémie Bardin ◽

Emmanuel Dartois ◽

Hugues Leroux ◽

...

Keyword(s):

Solar System ◽

Interplanetary Dust ◽

Cosmic Dust ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

Cometary Dust ◽

History Of ◽

Polar Snow ◽

Comet 67P ◽

Cometary Origin

AbstractComets are probably the best archives of the nascent solar system, 4.5 Gyr ago, and their compositions reveal crucial clues on the structure and dynamics of the early protoplanetary disk. Anhydrous minerals (olivine and pyroxene) have been identified in cometary dust for a few decades. Surprisingly, samples from comet Wild2 returned by the Stardust mission in 2006 also contain high temperature mineral assemblages like chondrules and refractory inclusions, which are typical components of primitive meteorites (carbonaceous chondrites - CCs). A few Stardust samples have also preserved some organic matter of comet Wild 2 that share some similarities with CCs. Interplanetary dust falling on Earth originate from comets and asteroids in proportions to be further constrained. These cosmic dust particles mostly show similarities with CCs, which in turn only represent a few percent of meteorites recovered on Earth. At least two (rare) families of cosmic dust particles have shown strong evidences for a cometary origin: the chondritic porous interplanetary dust particles (CP-IDPs) collected in the terrestrial stratosphere by NASA, and the ultracarbonaceous Antarctic Micrometeorites (UCAMMs) collected from polar snow and ice by French and Japanese teams. Analyses of dust particles from the Jupiter family comet 67P/Churyumov-Gerasimenko by the dust analyzers on Rosetta orbiter (COSIMA, GIADA, MIDAS) suggest a relationship to interplanetary dust/micrometeorites. A growing number of evidences highlights the existence of a continuum between asteroids and comets, already in the early history of the solar system.

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In situ 3-D mapping of pore structures and hollow grains of interplanetary dust particles with phase contrast X-ray nanotomography

Meteoritics and Planetary Science ◽

10.1111/maps.12674 ◽

2016 ◽

Vol 51 (9) ◽

pp. 1632-1642

Author(s):

Z. W. Hu ◽

R. P. Winarski

Keyword(s):

Phase Contrast ◽

Interplanetary Dust ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

X Ray ◽

Pore Structures

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Analysis of interplanetary dust particles by soft and hard X-ray microscopy

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20030101 ◽

2003 ◽

Vol 104 ◽

pp. 367-372 ◽

Cited By ~ 5

Author(s):

G. J. Flynn ◽

L. P. Keller ◽

S. Wirick ◽

C. Jacobsen ◽

S. R. Sutton

Keyword(s):

Interplanetary Dust ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

X Ray

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Digital 3D shapes suitable for the description of meteoroids

10.5194/epsc2021-306 ◽

2021 ◽

Author(s):

David Čapek ◽

Tomáš Kohout ◽

Jiří Pachman ◽

Robert Macke ◽

Pavel Koten

Keyword(s):

Solar Radiation ◽

Interplanetary Dust ◽

The Body ◽

Light Curves ◽

Dust Particles ◽

Interplanetary Dust Particles ◽

X Ray ◽

Yorp Effect ◽

Solar System Bodies ◽

3D Shapes

<p>Some processes in the physics of small solar system bodies depend on the detailed shape of the body. One of them is the YORP effect, which affects the rotation of asteroids and can lead to rotational bursting. The YORP effect can be modelled because the shape of asteroids can be determined from spacecraft images, radar observations, or inversions of asteroid light curves. A similar effect, caused by the reflection of solar radiation from an irregularly shaped body, affects the rotation of meteoroids. However, this effect is very difficult to model because we are not able to determine the shapes of meteoroids.</p> <p>In this presentation we show our approach to obtain shapes suitable for characterizing meteoroids. For meteoroids of asteroidal origin, we simulated their formation during a collision in the main belt by fragmentation a sample of an ordinary meteorite using explosive charge technique and performed the digitization of fragments. To describe the cometary meteoroids, we used the shapes of interplanetary dust particles determined by X-ray microtomography. Finally, we show a comparison of the ability of the two types of shapes (asteroidal vs. cometary) to be spun up by the solar radiation.</p>

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Organic matter in interplanetary dust particles

Proceedings of the International Astronomical Union ◽

10.1017/s174392130802173x ◽

2008 ◽

Vol 4 (S251) ◽

pp. 267-276 ◽

Cited By ~ 10

Author(s):

G. J. Flynn ◽

L. P. Keller ◽

S. Wirick ◽

C. Jacobsen

Keyword(s):

Organic Matter ◽

Infrared Spectroscopy ◽

Thermal Processing ◽

Interplanetary Dust ◽

Dust Particles ◽

Radiation Processing ◽

Interplanetary Dust Particles ◽

Edge Structure ◽

X Ray ◽

X Ray Absorption

AbstractAnhydrous interplanetary dust particles (IDPs), which are the most mineralogically primitive extraterrestrial materials available for laboratory analysis, contain several percent organic matter. The high O:C and N:C ratios suggest the organic matter in the anhydrous IDPs is significantly less altered by thermal processing than the organic matter in meteorites. X-ray Absorption Near-Edge Structure (XANES) spectroscopy and infrared spectroscopy demonstrate the presence of C=C, most likely as C-rings, C=O, and aliphatic C-H2and C-H3in all the IDPs examined. A D-rich spot, containing material that is believed to have formed in a cold molecular cloud, has C-XANES and infrared spectra very similar to the organic matter in the anhydrous IDPs, possibly indicating a common formation mechanism. However the primitive organic matter in the IDPs differs from the interstellar/circumstellar organic matter characterized by astronomical infrared spectroscopy in the relative strengths of the asymmetric aliphatic C-H2and C-H3absorptions, with the IDP organic having a longer mean chain length. If both types of organic matter originated by the same process, this may indicate the interstellar organic matter has experienced more severe radiation processing than the organic matter in the primitive IDPs.

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