Isotope anomalies provide important information about early solar system evolution. Here we report molybdenum isotope abundances determined in samples of various meteorite classes. There is no fractionation of molybdenum isotopes in our sample set within 0.1 per thousand and no contribution from the extinct radionuclide ~(97)Tc at mass 97 (~(97)Tc/~(92)Mo < 3 x 10~(-6)). Instead, we observe clear anomalies in bulk iron meteorites, mesosiderites, pallasites, and chondrites characterized by a coupled excess in p- and r-process or a mirror deficit in s-process nuclides (Mo-w). This large-scale isotope heterogeneity of the solar system observed for molybdenum must have been inherited from the interstellar environment where the Sun was born, illustrating the concept of "cosmic chemical memory." The presence of molybdenum anomalies is used to discuss the filiation between planetesimals.
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机译：同位素异常提供有关早期太阳系演化的重要信息。在这里，我们报告在各种陨石类别的样品中确定的钼同位素丰度。在我们的样品集中，每千分之0.1内没有钼同位素的分馏，并且质量97时灭绝的放射性核素〜（97）Tc没有贡献（〜（97）Tc /〜（92）Mo <3 x 10〜（-6 ））。取而代之的是，我们观察到大量铁陨石，中铁菱铁矿，方石和球粒陨石的明显异常，其特征是p和r过程耦合过剩或s过程核素（Mo-w）镜面缺陷。观察到的钼在太阳系中的这种大规模同位素异质性必须继承自太阳诞生的星际环境，从而说明了“宇宙化学记忆”的概念。钼异常的存在被用来讨论小行星之间的分iation。
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