Aeronomy (Greek word meaning "Study of Atmospheres") is a multidisciplinary field of study which studies atmospheric regions in which the processes of photo ionization and dissociation are important. During these processes, solar energy separates neutral atoms, molecules, and compounds into positive and negative particles. This occurs in atmospheres around the Earth, other planets, comets, and satellites.
The first to use the term Aeronomy in its modern context was the geophysicist Sydney Chapman in an article published by Nature in 1946, and it became officially accepted terminology after 1954 by the International Union of Geodesy and Geophysics. Aeronomy is a subdiscipline of atmospheric physics.
Aeronomy has a great importance to the life on Earth as the research conducted in this field directly applies to the study of global climate change, satellite communication systems, global positioning system (GPS) accuracy, and the interactions of space phenomena with terrestrial power distribution systems.
Research in aeronomy requires access to satellites, sounding rockets and specially stratospheric balloons which provide valuable data about this region of the atmosphere. On this regard the main balloon-borne instruments used in aeronomy includes interferometers, spectrometers, infrared detectors and others means for performing remote and in-situ observations.
Some keys elements of the aeronomy research includes the study of atmospheric tides that dominate the dynamics of the mesosphere and lower thermosphere, upper-atmospheric lightning discharges, such as red sprites, sprite halos, blue jets, and elves and the interaction of the solar wind with the high atmosphere.