Lightning is a beautiful but dangerous phenomenon. Many think it is white, but is it really?
Lightning is a giant electric discharge. Strong winds cause ice crystals and liquid water drops to rub against each other. Electrons strip off when this happens, thus the ice crystals and the water particles become either positively or negatively charged. Then, the negative charges usually sit at the bottom of a cloud, while the positive charges are at the cloud’s top. These charges form an electric field. When the difference in charge becomes too great, a lightning bolt forms.
Electrons flowing through a lightning bolt create a plasma, or ionized gas, that can reach temperatures of 50,000 degrees Fahrenheit. This plasma emits a spectrum of electromagnetic energy in the form of radio waves and gamma rays. Instruments that measure electromagnetic waves helps scientists detect far-away lightning bolts.
Lightning that strikes the ground emits all wavelengths of light, but most of the visible light is blue. Over the last 20 years, scientists discovered lightning can also shoot upwards above thunderstorms. This lightning mainly gives off wavelengths of light red or blue. However, when we look at lightning, our eyes are filled with an intensity of all wavelengths of light, so we perceive lightning as the white.
Lightning may last for just a flash, but it really is a cool and complex phenomenon.
[Source: Wisconsin State Journal]