Scale height — A parameter for characterizing atmosphere

Scale height is a parameter used to describe how something fades away with increasing distance. It is exclusively applied to atmospheres1 of terrestrial planets and moons in this paper, but it is used in many other contexts, e.g., describing the distances of various types of stars from the galactic disk.2 It brings together diverse concepts such as hydrostatic equilibrium, the ideal gas law, and the acceleration due to gravity to describe the extent to which an atmosphere hugs its parent body.