Astronomy 1021 Chapter Notes - Chapter 7: Solar Wind, Outer Core, Electromagnet
Document Summary
The earth"s surface is very changeable from earthquakes to volcanoes to asteroids to rivers. All the terrestrial planets would have looked similar at their creation: differences must be due to changes. Why is earth geologically active: this means earth"s surface is continually being reshaped by volcanic eruptions, earthquakes, erosion, etc, interior structure. Seismic waves: vibrations that travel both through and on the surface after an earthquake. Core: highest density material, consisting primarily of metals (such as nickel and iron) residing in a central core. Mantle: rocky material of moderate density (mostly minerals such as silicon and oxygen) forms a thick mantle that surrounds the core. The very top of the mantle is called the lithosphere". It is a cool and rigid rock that essentially floats on warmer softer rock beneath. Granite and basalt (common form of volcanic rock)) forms a thin crust. Earth"s core consists of a solid inner core and molten outer core.