Not many things can be more pleasant than standing around a campfire. Hearing the wood crackle and looking at the constantly changing shapes created by the fire. You can stare at it forever.
You can feel the heat and the distinctive smell of smoke. But what exactly stands behind that experience? What you are looking at, what you are hearing and feeling?
Fire cannot be described as a solid matter. It is not a liquid too. We can accept it is a gas, but gases can exist here on Earth indefinitely without any change while all fires eventually burn out.
Some people believe fire is the fourth state of matter called plasma. But on our planet plasma cannot exist for too long. It can appear as thunders and some other phenomena but they disappear as fast as they have appeared.
Gases can turn into plasma when exposed on a magnetic field or temperatures of thousands or even tens of thousands of degrees but most materials we use as fuel burn at temperatures that are too far away from the needed ones.
It turns out fire is not a matter at all. It is just the experience we have when a chemical reaction is taking place. We see such reactions happening all around us. For example in autumn leaves change color, fruits ripen and many more.
What is special about fire is that the chemical reaction combustion is experienced by all of our senses. We hear the wood crackle when the trapped water inside is evaporating and leaving the wood. We feel the warmth released in the process. See the fire because it generates light. And we smell it because a lot of scents are released into the air while burning.
Every fire has its own special set of different experiences. For example, depending on the temperature of the fire, the color can range from red to white and blue. Some elements also add their colors to the mix.
For all of these experiences, combustion only needs fuel, heat, and oxygen. Fuel to burn it in the process, heat to keep the fuel above ignition temperature and oxygen to support the reaction.
Gravity also contributes to the beauty of fire. Without it, the flames do not separate and would look different.
But as mentioned above fires cannot exist forever. Even the biggest of them finally run out of fuel and disappear. Leaving only ash as a sign of their former beauty.
