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تسجيل مستخدم جديدMultiple carriers of Q noble gases in primitive meteorites
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The main carrier of primordial heavy noble gases in chondrites is thought to be an organic phase, known as phase Q, whose precise characterization has resisted decades of investigation. Indirect techniques have revealed that phase Q might be composed of two subphases, one of them associated with sulfide. Here we provide experimental evidence that noble gases trapped within meteoritic sulfides present chemically- and thermally-driven behavior patterns that are similar to Q-gases. We therefore suggest that phase Q is likely composed of two subcomponents: carbonaceous phases and sulfides. In situ decay of iodine at concentrations levels consistent with those reported for meteoritic sulfides can reproduce the 129Xe excess observed for Q-gases relative to fractionated Solar Wind. We suggest that the Q-bearing sulfides formed at high temperature and could have recorded the conditions that prevailed in the chondrule-forming region(s).
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The energy associated with giant impacts is large enough to generate global magma oceans during Earths accretion. However, geochemical evidence requiring a terrestrial magma ocean is scarce. Here we present evidence for at least two separate magma oc
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Presolar diamond, the carrier of the isotopically anomalous Xe component Xe-HL, was the first mineral type of presolar dust that was isolated from meteorites. The excesses in the light, p-process only isotopes 124Xe and 126Xe, and in the heavy, r-pro
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The determination of Saturns atmospheric noble gas abundances are critical to understanding the formation and evolution of Saturn, and giant planets in general. These measurements can only be performed with an entry probe. A Saturn probe will address
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