In Aristotelian physics, the term was applied to four spherical natural places, concentrically nested around the center of the Earth, as described in the lectures Physica and Meteorologica.
They were believed to explain the motions of the four terrestrial elements: Earth, Water, Air, and Fire.
[2] The different collectives of the geosphere are able to exchange different mass and/or energy fluxes (the measurable amount of change).
Since space exploration began, it has been observed that the extent of the ionosphere or plasmasphere is highly variable, and often much larger than previously appreciated, at times extending to the boundaries of the Earth's magnetosphere.
[4] This highly variable outer boundary of geogenic matter has been referred to as the "geopause" (or magnetopause),[5] to suggest the relative scarcity of such matter beyond it, where the solar wind dominates.