mical composition by studying chondrite meteorites; there are three kinds of these meteorites, and in the past it was wrongly assumed that Earth was like the wrong kind, the ordinary chondrites. The group of elstatite chondrites was ignored, which Herndon in the 1970s realized pointed to a nickel silicide core. Only elstatite chondrites have a high enough iron alloy to account for the core’s mass.
This article is related to the course material studied because it explains the composition of the Earth’s interior. This article provides knowledge of the six layers of Earth’s interior and what they are made up of. These layers are, in order: the rocky upper crust; the upper mantle (of unknown composition); the lower mantle, containing magnesium silicates (MgSiO3); the core floaters, containing calcium sulfide and magnesium sulfide (CaS and MgS); the fluid core, containing iron and sulfur (Fe and S); and the inner core, made of nickel silicide (NixSiy). In addition, uranium in the Earth’s core may set up a natural georeactor.
This article is important because it not only gives us the facts of the Earth’s composition, but it also relates how we came to know what we do about the Earth’s interior. This includes not only the logical progression towards that knowledge, but also illuminates the error involving the assumption that Earth was like the wrong kind of chondrite meteorite; this error slowed down our path to understanding what the Earth is made of. As the article shows, we have only explored the first 12.8 kilometers below the Earth’s surface, while there are 6771 kilometers to the Earth’s core. This means that we still have a lot to discover about the Earth’s interior. By examining how we have made progression in knowledge of Earth as outlined in this article, we should be better enabled to move in the right direction for future