Presolar grains in primitive Solar System materials

2 Presolar grains in primitive Solar System materials 

Presolar grains exhibit large isotopic anomalies not only in their major elements, but also in many minor elements. Isotopic ratios vary over many orders of magnitude, indicative of contributions from different types of stellar sources, namely evolved stars, novae, and SN explosions. Isotope anomalies are also seen in objects with Solar System origin, which, however, are much smaller than those in presolar grains. For example, the calcium-aluminum-rich inclusions (CAIs), the earliest 

4 Formation of dust from elements different from C, for instance formation of SiC, in stellar outflows ceases at 

Magellanic Cloud (Z = Zq) dust production is observed, see Zijlstra et al. (2007). 

Mineral Abundance1 (ppm) Stellar sources Relative contribution 

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