Mg Si Ratios of Stars in the Vicinity
Channel: Dominik Hezel
Date: 20/03/2020

*check out all videos and much more on metbase.org in the 'Resources' section*

Mg and Si are two main elements in our solar system. The Mg/Si ratios of stars in the vicinity of our solar system is close to the Mg/Si ratio of the Sun, which is about 1.07 (mass-ratio). Components that formed in the protoplanetary disk, such as chondrules, should therefore only contain olivine and pyroxene. Some addition of Fe to these minerals would further increase the olivine/pyroxene ratio. No silica is expected. The silica observed in chondrules, must therefore represent the result of a fractionation process. Observations of protoplanetary disks have also shown the presence of silica. As their Mg/Si ratio is similar to our solar system, the same argument can be made, i.e., the observed silica must represent the result of a fractionation process. Hence, it appears similar process formed the first solids of various protoplanetary disks, including our own.