It is now recognized that pickup ions are present in almost all possible space environments, created from atoms originating at comets, planets, the satellites of the gas giants, and the interstellar medium. Indeed, pickup ions can be formed whenever a neutral gas and plasma interact.

Over the past three decades, the physics and consequences of pickup ions has been studied in considerable detail, ranging from artificial comet experiments (AMPTE) in the Earth's magnetosphere, to interplanetary missions to comets Halley, Giacobini-Zinner, and Grigg-Skjellerup, the planets Venus and Mars and the satellites of Jupiter and Saturn, to the outer heliosphere and the solar wind-local interstellar medium boundaries (heliospheric termination shock, inner and outer heliosheath).