Our science books never told us about the 4th state of matter. We didn’t know this but it exists as an integral part of our everyday life, and that’s why we need to know about it.
Another state of matter? Where?
It exists at temperatures much higher than gas temperatures, or at much higher pressures, such that the gas becomes electrically/magnetically charged, in a way that the net charge in the gas is almost equal to 0.
Now that we know what it is, let’s see how it affects our lives.
Auroras occur when Plasma from the Sun (Solar Wind) enters earth’s magnetic field. As the earth’s magnetic field converges at the poles, the plasma from sun comes in contact with the atmospheric gases at these places only. And when it does, it discharges its energy to these gases like Nitrogen and Oxygen.
Then what happens is these gases get excited of this energy, so to release this energy they release lights. This causes a splendid display of dancing colours in the upper atmosphere called the Aurora Lights. For more on this, read our chapter on light.
Another plasma that we see in our daily lives is lightning. As we know, air is a bad conductor of electricity, but when lightning strikes, air acts as a conductor.
The charge accumulated inside the cloud is so much that to release its charge it charges air particles in the way, converting the air into plasma. Charge accumulated on the cloud travels through this plasma. When the charge has passed, the gas releases the energy it accumulated due to ionization by releasing light. That is called lightning!
Yes, Nuclear Fusion happens every day in our lives. The sun is producing all that energy through fusion. That is fusion of deuterium atoms (or deuterium and tritium) to form helium.
I’m not going to bore you with equations, just know that 2 deuterium atoms combine to form helium, which needs less energy to stay as a single atom, so the reaction is exothermic.
It doesn’t happen at normal temperatures, for nuclear fusion to happen a very high temperature is required. At this temperature, gases cease to possess any kind of binding forces, and the hydrogen is always ionised, forming plasma. So even the hydrogen (deuterium) to remain hydrogen (i.e. have electrons as well, and not only nucleons), gives out energy in the form of light, however short lived its existence may be. But the light we see is majorly due to the energy released as a product of fusion.
This is important because to create a stable nuclear fusion reaction on earth, we need to maintain a plasma. Only then can we produce energy with it. Scientists haven’t achieved it yet (for commercial purposes), and are constantly working on making nuclear fusion possible for things other than the atomic bomb, as it is a clean source of energy, and would prove to be a major help in this age of increasing energy demands.