Atem Study of Four Thermally Modified Stardust Particles from Track
نویسندگان
چکیده
Introduction: The Stardust mission brought to earth samples from the comet 81P/ Wild 2. The cometary material is believed to be the most primitive material in the solar system and the return of the samples provides information about the prevailing conditions of the early solar system. The samples have been trapped in silica aerogel at 6.1km.s and the hypervelocity impacts have generated deceleration tracks in the aerogel [1] along which the cometary material is unevenly distributed in various proportions [1-3]. The deceleration induced a heat increase that modified the sample microstructure [4-7]. For number of samples, the microstructure gives clear evidence of melting of the cometary dust and mixing with molten aerogel. We know that the particles have been modified during the collect but what is the extent of the thermal-induced modification? Is it possible to deduce the original particle size and composition? The aim of this work is to characterize samples from a single parent track (#80), in order to firstly, compare their relative microstructure and chemical composition, and secondly, gain in the understanding of the modification evolution during the deceleration.
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