Crust (geology) formed almost immediately after formation of the Moon. Magmatism continued after the period of intense meteorite impacts ended about 3.9 billion years ago, but igneous rocks younger than 3.9 billion years make up only a minor part of the crust. Crust (geology) In geology, the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite. It is usually distinguished from the underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be distinguished based on its phase (solid crust vs. liquid mantle). The crusts of Earth, Moon, Mercury, Venus, Mars,
Do Not Ask What Good We Do Do Not Ask What Good We Do Do Not Ask What Good We Do: Inside the U.S. House of Representatives is a 2012 book by the author Robert Draper and published by Free Press. It details the activities of Republicans and Democrats in the United States House of Representatives and the Senate during the first term of Barack Obama's presidency. The book was republished under the title When the Tea Party Came to Town. In order to research the activities and politics within the House of Representatives, Draper "embedded with new and senior House members" that had been elected in