Plasma is the most common state of matter in nature, accounting for about 99% of the mass of the universe. However, the science itself, which studies this aggregate state of matter, is only 80 years old. That’s how much time has passed since Nobel laureate Irving Langmuir first used the word “plasma”.
What is plasma
The state of matter changes with temperature. For example, water at negative (on the Celsius scale) temperatures is in a solid state, in the range from 0 to 100 ° C – in a liquid state, above 100 ° C – in a gaseous state. If the temperature continues to rise, atoms and molecules begin to lose their electrons – they become ionized, and the gas turns into plasma. At temperatures above 1,000,000 °C, the plasma is completely ionized—it consists only of electrons and positive ions.
The sun, most stars, nebulae – they are all composed of fully ionized plasma. The outer part of the earth’s atmosphere – the ionosphere – is also made of plasma. Auroras, lightning, including balls, are all different types of ionized gas that can be observed in natural conditions on Earth.
In late 1928, Irving Langmuir first used the word “plasma” to refer to what is now commonly called the fourth state of matter. In his work for the US National Academy of Sciences, he designated by this neologism “a state containing a balanced charge of ions and electrons.”
The very word “plasma” is borrowed from the Greek language and means “fashioned, formed.” The ancient Hellenes called this phoneme bright lightning that forms a complex pattern in the sky.
History of Plasma Studies
The fourth state of matter was first obtained in 1879 by the English chemist and physicist Sir William Crookes. However, in order to develop a clear scientific understanding of the nature of plasma, it took almost thirty years.
It is now known that plasma is a fully or partially ionized gas, the total charge of which is equal to or tends to zero. However, the separate existence of ions and electrons in a gas endows the plasma with properties that are different from the usual gaseous state.
The work of Irving Langmuir formed the basis of plasma physics – his first experiments in this area included studies of the electrical conductivity of plasma and its reaction when interacting with magnetic fields.
The ionized gas itself until the mid-70s was considered a kind of “panacea” capable of solving all the energy problems of mankind. Later, another unique property of plasma was discovered – it is able to clean and sterilize any surface at the atomic level, replacing traditional “wet” chemical methods.
Plasma technologies have a wide range of applications, especially in the field of controlled nuclear fusion. In everyday life, plasma is less common. The only practical plasma-based home product is the gas discharge display, more commonly known as a “plasma panel”.