Plasmas and Dust

Abstract

Life on the surface of the Earth has made us familiar with three states of matter, the solid, liquid and gas phases. The transition is easily described in terms of increasing temperatures, whereby the constituent atoms and molecules have ever more freedom of movement. When the atoms in a gas are heated further and accumulate enough energy, they decompose into ions and electrons and the gas becomes fully or partially ionized. We have thus reached the plasma state, in this picture the fourth state of matter. Ancient man recognized four holy elements: Fire, Earth, Water and Air, and the latter three readily symbolize the solid, liquid and gas states of matter. What about Fire? The flame of a burning candle is ionized, as we now know, and thus a plasma. Even better, it is contaminated with soot and other remnants of the burning material, and as such, a perfect example of a dusty plasma.