Growing up, one of my summer highlights was attending the fireworks celebration on the 4^th of July.  We lived near a big lake, and the brilliant sights and sounds of the colors and noises are etched in my memory.  Once we had our own family and the kids were old enough, my husband and I started that same tradition. We all loved the experience, but never considered the science behind it. It turns out fireworks include chemistry, physics, and even a bit of biology!

The Science Behind the Show

The study and making of fireworks is called pyrotechnics, covering everything from simple sparklers to extensive sky displays set to music.  

Meet the Pyrotechnician: The Fireworks Expert

A pyrotechnician is specialist working behind the scenes to create the colorful light show we enjoy.  He pays close attention to colors; dark colors like blue and black won’t work- you wouldn’t be able to see them!  Instead, he uses chemicals to create bright, colorful explosions, with deep reds, glittering purples, and blazing greens.

Manufacturers pack small pellets packed with different chemical compounds that release different wavelengths of light to produce different colors.  The compounds are placed in a specific order and pattern to create different shapes and sizes.

Take a look at some of the chemicals used in fireworks and the colors they produce when ignited:

Firework Elements and Colors Explained

Each of these elements burn differently to produce varying colors and intensities of light.

The Physics of Fireworks: Trajectory, Timing & Safety

Pyrotechnicians are also trained in safety.  Because fireworks are propelled into the air by gunpowder, lighting a firework creates a launch like a rocket.  Experts need to learn different physics concepts that help them launch fireworks up and away from people, exploding at a height that is not dangerous to spectators.  They need to consider speed, trajectory, and gravity when creating an explosion. They take great care in making sure a fuse, which is a string or wire that is lit by a match or lighter, is long enough to burn safely.  

How Fireworks Whistle and Boom

To add sound effects, fireworks need to produce a gas very quickly. If the fireworks have a small opening to let the gas out, it will produce a high-pitched whistle.  If an entire firework explodes, you will hear a loud, sometimes earth-shaking boom.  Timing is important, both for the safety of the crowd and their enjoyment of the fireworks!

Biology and Brain Science: Why Fireworks Are So Thrilling

When we see awe-inspiring displays like fireworks, our brains release a chemical called dopamine.  Dopamine makes us feel that same sense of pleasure, no matter how many times we experience the thrill of fireworks. That means whether we’ve attended the 4^th of July fireworks celebration one time or fifty, we can enjoy it the same way!

Appreciating the Science Behind the Spectacle

When you watch the fireworks this year, take a moment to appreciate the science behind them that make them safe and spectacular- chemistry, physics, and biology.  Planning, creativity, precision, and science blend into an awe-inspiring display that never gets old!