Man-made plasma can be found in a rocket exhaust

Plasma is an ionized substance also known as the fourth fundamental state of matter after solid, liquid, and gas. Like gases, plasmas flow freely and expand to fill the containing space. Because plasmas consist of free-flowing ions and electrons, they are good electrical conductors and are influenced by electric and magnetic fields in unique ways different from other states of matter. Plasma state can be reached, for example, by heating matter to a very high temperature at which electrons can be stripped from atoms, by subjecting matter to radiation or too strong electric, magnetic or electromagnetic fields.

Naturally occurring plasma can be found in lightning, the Earth ionosphere, polar auroras, stars, accretion discs, solar wind, interplanetary and interstellar medium. Plasma can also be artificially produced. Man-made plasma can be found in a rocket exhaust, ion thrusters, plasma TVs, fluorescence lamps, ozone generators, electric arcs, and many more. Thanks to the unique properties of plasma it has a wide range of applications in industry, science, and daily life. Some of those applications include plasma spraying, plasma-enhanced chemical vapor deposition, reactive ion etching, surface cleaning, sterilization of fresh produce in the food industry, plasma cutting, electric arc welding, waste processing, metal recovery, plasma medicine, plasma propulsion, and fusion energy research.