1The Giant Air Explosion
When you see a flash of lightning, you are witnessing one of the most powerful events in nature. But the noise that follows, the thunder, is actually a giant air explosion! A bolt of lightning is incredibly hot—reaching temperatures of up to 30,000 degrees Celsius. That is five times hotter than the surface of the sun! This extreme heat makes the air around the bolt expand so quickly that it creates a massive shockwave. This shockwave is what we hear as the booming sound of thunder.
2Light Speed vs. Sound Speed
Have you ever noticed that the light always comes before the sound? That is because light is the fastest thing in the universe, traveling at an incredible 186,000 miles per second. Sound is a bit of a slowpoke by comparison, moving at only about 750 miles per hour through the air. Because light travels so much faster, the flash of lightning reaches your eyes instantly, while the sound waves of the thunder have to travel across the sky to reach your ears. The longer the gap between the flash and the bang, the further away the storm is.
3Why Does Thunder Rumble?
If lightning is very close, the thunder sounds like a sharp, loud crack. However, when a storm is far away, it sounds more like a low, rolling rumble. This happens because the sound waves are bouncing off clouds, trees, and buildings as they travel toward you. These echoes reach your ears at slightly different times, stretching the sound out into a long rumble. By counting the seconds between the lightning and the thunder, you can even estimate the distance: for every five seconds you count, the storm is about one mile away!
