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Virtual Pressrooms (VPR) offer Meeting news, highlighted papers, images, and videos from APS Meetings. Journalists can access all these features without actually attending the Meeting.
The APS DPP Meeting showcases cutting-edge research results in plasma physics.
Solid, Liquid, Gas, and Plasma
Most of the matter with which we are familiar in everyday life exists in one of three states - solid, liquid, or gas. But much more of the matter in the universe exists in a fourth state known as plasma. Plasmas are collections of electrically charged particles such as electrons and protons, and typically exist in a gaseous state. Stars (including the sun), the space between the stars, nebulae, and the space environment near Earth are primarily composed of hot plasma.
A plasma is formed by breaking up the atoms and molecules in a gas, a process called ionization. Ionization requires adding energy to the gas, typically by passing electrical current or microwaves through it. On Earth, plasmas are created by people every day when they turn on fluorescent light bulbs or plasma-screen TV's. Bolts of lightning are comprised of plasma produced when large electrical currents pass through the atmosphere. In these examples, the plasma emits light.
Plasmas are used to inscribe the patterns in silicon from which computer chips and other electronics are made; and they are at the heart of the most promising nuclear fusion devices that may someday lead to an abundance of cheap, clean, and safe power sources. Plasmas are being used in medicine, and understanding plasmas helps prepare us for the damaging effects of space weather.