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
A Planet Called Utopia A Planet Called Utopia A Planet Called Utopia is a science fiction novel by Scottish writer J. T. McIntosh, first published in August, 1979 in New York by Zebra Books. It is the last book published by the author. Except for radio and television signals, which are tightly screened, it has been over sixty years since the last visitor was allowed into Utopia, a world where everyone was immortal. So that the world's population would not outrun available surface area, marriage has been outlawed (because couples start to want to have a child), lifelong romances discouraged (for pretty much the