Lightning is a light phenomenon that appears in the sky on cloudy days, and this light results from the collision of two clouds, one of which carries a positive electric charge and the other carries a negative electric charge, or from an electrical discharge that occurs from one cloud to another, or between parts of a single cloud, or from a cloud of clouds to ground. In this electrical discharge, a strong spark is generated that appears in the form of light that we suddenly see, then quickly fades and after a short period a loud sound called thunder is issued. Lightning here occurs in the sky because the discharge of the charge occurs in the sky. Lightning raises the temperature of the air around it to about 20 thousand degrees Celsius and produces a shock wave that is faster than sound, which reaches us as a sound wave we call thunder.
The speed of lightning varies between 60 and 1600 kilometers per second, that is, half the speed of light, its current ranges from a few thousand to about a hundred thousand amperes, and the average electrical voltage is about one hundred thousand volts. Lightning is not harmful unless it is transmitted from clouds to the ground, as it may infect people, their homes and their farms. Therefore, the lightning rod is used above high places. It is a copper pole with a pointed tip and is installed at the top of buildings and connected to a thick metal wire that ends with a metal plate buried underground in order to transmit the electric current and discharge the charge in the ground.
Lightning through history
Lightning has been occupying human thinking since the dawn of history, and many legends have been put forward about it because man saw it as frightening. For example, the Greeks attributed the occurrence of lightning to the gods Zeus and believed that he was using it to intimidate enemies and take revenge. The ancient civilizations also competed to link lightning with fairy tales, myths and religious beliefs, and myths remained dominating people’s minds before the arrival of heavenly messages. It is worth noting that lightning, thunder, thunderbolts, storms and rain were mentioned in the Holy Qur’an in many verses. The association of lightning with fear and greed has been repeated twice in the Qur’an, as lightning may have a lot of good and may be harmful, so a person fears it and warns him.
Serious attempts to understand lightning scientifically began in the eighteenth century, scientifically proven lightning in 1752 AD by the scientist Benjamin Franklin through the dangerous kite experiment that lightning is electrical in nature and that it is a spark that results from the meeting of two opposite charges. Very dangerous, and some scientists were exposed to direct injury from lightning, including the scientist George Richman, who died instantly from a lightning strike, and with time, tools and means developed and became safer until artificial lightning was generated, such as that done by the scientist Nikola Tesla in 1900 AD, and so the research continued And experiments until many details were reached about the origin of lightning, the causes of its formation and its types.
The difference between lightning and thunder
The difference between them is very simple. Lightning is the optical phenomenon that we see when an electrical discharge occurs between clouds, as we talked about previously. As for thunder, it is the sound phenomenon resulting from this discharge. It is known that light is faster than sound, so we see lightning before we hear thunder.
The difference between lightning and thunderbolt
The difference between lightning and thunderbolt lies in that the lightning occurs between the different parts of the clouds in the sky, but in the case of a thunderbolt, the electrical discharge occurs between the clouds carrying positive charges and the ground carrying negative charges. The thunderbolt may cause human death or serious damage to him and his property, and may cause forest fires, the duration of the thunderbolt does not exceed a tenth of a second and its temperature may reach 15,000 degrees Celsius, knowing that the surface temperature of the sun is only 8000 degrees Celsius. It is dangerous to walk in open places that do not have high places during lightning strikes. As for houses and buildings, the danger of lightning can be removed by using the lightning rod that we mentioned above above these facilities.
types of lightning
- Cloud-earth lightning, which results from the fact that the cloud’s charge near the Earth is negative and the Earth’s surface has a positive charge, and this is the lightning strike that strikes the Earth.
- Cloud lightning – a cloud, occurs between clouds of different charges, and is the most common and widespread in various parts of the world.
- Cloud-air lightning, which occurs when there is a difference between the charge of the cloud and the charge of the air surrounding it from one side. It is difficult to notice this type of lightning.
- There is lightning that occurs within the same cloud due to the difference in the charge between its two ends and the occurrence of contact between them in certain circumstances in thunderstorms. There are also many types of lightning such as ribbon lightning, beaded lightning, choppy lightning, branched lightning, ghost lightning, paper lightning, thermal lightning, dry lightning, missile lightning, ball lightning, blue jet lightning, dwarf lightning, and others.
Lightning and bodies of water
Statistics and studies carried out by NASA showed that the majority of lightning cases occur on land only, although the predominant area on the Earth’s surface is the area of water bodies. This is because the thunderbolt is looking for the shortest path and the land is often higher than sea level. Even if lightning strikes water bodies, marine organisms survive because lightning does not penetrate the water surface for deep distances under the influence of a phenomenon called the crust effect. As this phenomenon is responsible for transforming the surface of the outer conductor into an element so that the conductor’s specific resistance increases. Salt water in this case resists the current more than a metallic conductor.
- Lightning and rain both contribute to purifying the atmosphere of dust, pollen, pollutants and germs. So you can enjoy the clean air after the thunderstorm is over.
- The heat and pressure associated with lightning helps convert nitrogen and other gases in the atmosphere into beneficial compounds such as nitrogen oxides and nitric acid. These compounds fall from rain and mix with the soil to act as a useful natural fertilizer for plants.
- Lightning helps rain fall and irrigate crops, and it helps condense dust particles that facilitate the process of condensation and rain. Likewise, lightning generates very high heat in a short time, as mentioned above, and this heat heats the surrounding air and this leads to a rapid drop in atmospheric pressure, and this is the ideal environment for rain, so we notice that large raindrops fall after lightning in most cases.
- Photography of lightning is a hobby for many amateurs and professionals in the art of photography, and this photography has helped scientists to study this phenomenon extensively, and many of these photographers and those interested deal with it as a wonderful natural painting.
- Lightning generates heavy water, “oxidized water”, which consists of additional amounts of oxygen, and this water is very useful to eliminate germs, and is used medicinally in disinfecting wounds and this water eliminates agricultural pests when it falls on the ground, so it is said that the lack of thunder and lightning increases plant pests .
How does lightning occur?