Abundance of the chemical elements in the Sun and outer planets is similar to that in the universe. Due to solar heating, the elements of Earth and the inner rocky planets of the Solar System have undergone an additional depletion of volatile hydrogen, helium, neon, nitrogen, and carbon (which volatilizes as methane). The crust, mantle, and core of the Earth show evidence of chemical segregation plus some sequestration by density. Lighter silicates of aluminum are found in the crust, with more magnesium silicate in the mantle, while metallic iron and nickel compose the core. The abundance of elements in specialized environments, such as atmospheres, or
Geology of the Moon of this, it has been noted that the largest crustal magnetizations appear to be located near the antipodes of the largest impact basins. Although the Moon does not have a dipolar magnetic field like Earth's, some of the returned rocks do have strong magnetizations. Furthermore, measurements from orbit show that some portions of the lunar surface are associated with strong magnetic fields. Geology of the Moon The geology of the Moon (sometimes called selenology, although the latter term can refer more generally to "lunar science") is quite different from that of Earth. The Moon lacks a significant atmosphere, which eliminates