Laboratory studies of Solar System dust

The dust of the early Solar System accreted to form the planets, moons, asteroids, and comets that are seen today. However, most of the bodies of the present-day Solar System have experienced significant thermal or aqueous processing, which modified the original dust, overprinting the record of early solar nebular events. A few primitive bodies, including some meteorites, interplanetary dust particles (see Fig. 6.1), and comets, are relatively unmetamorphosed. The examination of these samples provides the opportunity to examine relatively well-preserved dust from the early Solar System. 

Minerals are identified by a variety of techniques. Some minerals can be identified on the basis of their elemental compositions, but diffraction or X-ray absorption near-edge structure (XANES) spectroscopy provides more compelling mineral identification. Diffraction patterns, produced either by electron or X-ray beams, provide a direct measurement of the spacing between planes of atoms in the crystal structure. When coupled with element analysis, diffraction provides mineralogical identification. 

Atoms in a molecule vibrate with well-defined frequencies that are characteristic of the particular bond or functional group. In infrared spectroscopy the sample is 

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