Atmosphere of Earth (see the temperature section, below). Because the general pattern of the temperature/altitude profile is constant and measurable by means of instrumented balloon soundings, the temperature behavior provides a useful metric to distinguish atmospheric layers. In this way, Earth's atmosphere can be divided (called atmospheric stratification) into five main layers. Excluding the exosphere, the atmosphere has four primary layers, which are the troposphere, stratosphere, mesosphere, and thermosphere. From highest to lowest, the five main layers are: The exosphere is the outermost layer of Earth's atmosphere (i.e. the upper limit of the atmosphere). It extends from the exobase, which is located at
The World We Live In (Life magazine) by "The Epic of Man", focusing on the development and history of human civilization, and "The Wonders of Life on Earth", a series of articles tracing Darwin and evolution. Both of these were written by Barnett as well, and featured many of the same artists. "Life"'s series on the International Geological Year was hailed as a spiritual "update" to "The World We Live In". The World We Live In (Life magazine) The World We Live In appeared in the pages of LIFE magazine from December 8, 1952, to December 20, 1954. A science series, it comprised 13 chapters published on