Glow sticks have been a fascinating accessory for both young and old for almost four decades. They come in different shapes, colors, and sizes and are commonly known as a fun gimmick for audiences at nighttime events, such as music concerts or parties, to create an engaging atmosphere. However, besides entertainment purposes, glow sticks can be used in many practical ways as well. In fact, the US Department of Defense is the biggest consumer of glow sticks today.
The Inventors of Glow Sticks
On an early summer night when dusk hits and tiny glowing lights begin to flicker, floating through the night wind, it’s hard not to be enamored with the simple glow of a firefly as it hovers close, just within reach. Though they may technically be tiny flying beetles, not many will argue that fireflies, or lightning bugs, are not enchanting and beautiful creatures. In fact, they could be considered “inspiring.” Fireflies were, in fact, the inspiration for the invention of numerous chemical glow products like glow sticks.
The idea was first conceived by a chemist named Dr. Edwin Chandross, a scientist who aspired to recreate one of the simple beauties of nature by causing a chemical reaction that would produce a glowing light. It turns out that the light produced by fireflies was bioluminescence, which can only be produced by a living organism, but the light that Chandross would discover was the product of chemiluminescence.
During his college years, Chandross studied science at MIT and was turned on to a curious chemical while watching an experiment – luminol.
Luminol is a chemical that creates a blue glow in reaction to an oxidizing agent. This chemical reaction is activated quickly and only lasts for a short period of time before the light dims and then disappears. To give you some perspective on the practical use of this chemical, luminol is commonly used by investigators at crime scenes to detect the blood of victims or perpetrators to be tested for evidence. This is done by spraying the chemical across an area in darkened or dimmed light; if blood, among other oxidizing agents, is on the area sprayed, the luminol will react with it by emitting a blue glow for about thirty seconds before fading away. This is not a precise method for detecting blood because there are many other substances besides blood that can activate luminol to exhibit a glow, and other factors in the environment can effect its reactions as well. However, any trace detection is useful and luminol is still being used this way today.
After the knowledge of luminol sparked an interest in Chandross, he dedicated much of his studies throughout undergraduate and graduate school to chemiluminescence. After graduating from Harvard with a master’s degree in organic chemistry, Chandross joined Bell Labs (created by scientist Alexander Graham Bell himself) in New Jersey, where he continued his studies on the science of light, including developments that led to the discovery of fiber optics and the technology used for LED TVs. It was there, during the 1960s, that glow sticks were discovered – by accident.
In an effort to solve a practical problem at the lab, Chandross discovered an active luminescence-producing combination by experimenting with hydrogen peroxide and chloride. Several chemists, intrigued by this discovery, experimented further with Chandross’s concoction until it could be put in to practical use in many different forms – one of which was the glow stick.
Unfortunately, Dr. Chandross never patented his discovery and was never officially titled as the inventor of “chemical light.” In 1976, scientists Vincent J. Esposito, Steven M. Little, and John H. Lyon received a patent on their discoveries, which were based on those of Dr. Chandross, and were deemed the inventor’s title.
More than Just Fun
Glow sticks are generally thought of as party decor, kids’ toys or prizes, accessories related with fireworks on Independence Day or flashy jewelry for night events. Most can agree that holding a glowing stick of light in your hands is great for simple fun in the dark and can set a great mood for any party. You’d be surprised, though, what glow sticks can be used for in a number of practical capacities.
The world of sports is a growing field for glow sticks. Fishermen have found use for glow sticks as both visibility aids and as an added attraction for fish. For early morning or late night anglers, the light stick works as a float (or bobber), marking the position of the fishing line in the water. As with flashy lures coated with bright, neon colors, sparkles or metallic shimmer, the fish are drawn to the beautiful light of a glow stick right before they take their last bite. Likewise, golfers took advantage of glow product innovations by creating the “ultimate golf ball,” a ball that glows up to twelve hours and allows the athletes to putt in the dark, even on an outdoor course. Of course, many non-golfers or casual golfers are probably more likely to have seen this translated into the realm of birthday parties and weekend activities with the creation of glow-in-the-dark mini-golf. A number of sports, from volleyball, to soccer, to football, have been given the opportunity for a twist or two on the original by allowing for night sports through glow-in-the-dark balls, equipment and clothing. Even if not used for professional games, these items provide great opportunities for sports professionals to get creative, to think out of the box and to have some extra fun doing what they love. Having the option for night sports invites the possibility for new sports to be developed too, which is both beneficial and exciting for the industry.
As far as practicality goes, emergency lighting is probably the most important role that a glow stick can play. A great place to keep glow sticks is in a storage compartment in your car, motorcycle, or any other vehicle used for transportation. Glow sticks can be used as a reliable light source if your vehicle breaks down or if you’re involved in an accident. They serve as an excellent substitute for road flares to signal passing drivers who may not see your vehicle in the dark. (They’re much safer without the open flames, too.) In the same situation, they can be used as a great source of light to check on the engine or other car parts. Why choose glow sticks over flashlights or cell phones? Although they’re made for one-time use, glow sticks actually last longer and are more durable than the batteries in a flashlight and last a lot longer than a phone using a flashlight app (while you’re probably better off using it to call a tow truck or get help from a friend), making them a safer and more reliable choice when you’re preparing for any possible emergency situation.
And speaking of emergencies, glow sticks have proven to be an indispensable item when disaster hits. Earthquakes, tsunamis, hurricanes – rescue teams for numerous types of natural disasters have utilized glow sticks for their usefulness in almost any environment. Disasters can rarely be foreseen or avoided quickly enough, but being prepared for them is the key to survival. Many survival kits include glow sticks for a source of light, whereas in the past, only emergency candles were available. Although candles are useful in a similar way, glow sticks are more accessible since they don’t need to be lit by a flame, can be carried easily if you’re on the move during a disaster, are not affected by rain, snow, or underwater conditions and are generally safer because there is no risk like that of an open flame. In fact, because the light that emits from a glow stick is chemically produced, cold weather conditions will actually lengthen the life of the product as the colder temperatures slow down the chemical reaction and allow it to last even longer. Compact, lightweight, sturdy, long-lasting and versatile, glow sticks are the ultimate resource for lighting needs in extreme scenarios. Search and Rescue teams have caught on to this as well, not only including glow sticks in their emergency packs, but also manufacturing rescue gear, such as vests, suits and lifejackets with pockets and straps specifically designed to carry glow sticks. Even rescue vehicles, such as lifeboats, are decked with glow sticks to emit light, ensuring visual contact between rescue team members even in low-visibility situations.
These small, child-like toys are playing a big part in new developments made to bring faster and more efficient disaster relief when nature strikes. And despite the recent climb in the use of glow sticks during natural disasters, the US Department of Defense is an even bigger player in the market of glow. The DOD equips its soldiers with glow sticks for numerous uses and consumes an average of 20 million light sticks per year. When glow sticks were first introduced into the US military, they were aptly utilized as emergency lights, warning lights and as marking devices for various targets. They’ve been used as make-shift landing strips for aircraft, as visual marks for night parachuting, and as color coding for people and items during night missions. Since then, the military has gradually expanded its usage of glow sticks and other chemical light products. Glow sticks are being used for tactical and night operations, for marking team movements and even as a substitute for night vision on weapon scopes. In recent years, infra-red glow sticks have been specially developed for the military for covert operations, such as marking targets without detection since the infra-red light would only be visible with the correct eye gear. As chemical light developments progress, it’s expected that the military will continue to discover even more resourceful ways to use glow sticks and other glow products.
How Do Glow Sticks Work?
Most chemical reactions release energy in the form of warmth. The chemical reaction in a glow stick, however, produces energy in the form of light. This process is called chemiluminescence, including the Latin word “lumen” (English: “light”). The outer capsule of the glow stick is made of polyethylene, a thermoplastic synthetic material that can be melted into a liquid and remolded as it returns to a solid state. This is just the casing for the chemicals; the reaction produced when the chemicals combine is where the magic happens. The casing consists of two separate chambers filled with two different chemical liquids. The inner chamber is a thin glass tube that swims in the chemical the exterior chamber is filled with. Now, as you bend the glow stick, the glass tube breaks and releases the internal chemical, which then reacts with the outer chemical to produce a chemical light – chemiluminescence. The long-lasting reaction we see in a glow stick is based on the oxidative release of nitrogen from luminol coming into contact with hydrogen peroxide and sodium hydroxide, which are contained in the glass tube until broken. Heat is not produced in this reaction, which makes the glow stick a convenient replacement for light bulbs that can get so hot that they burn your fingers and candles that pose the risk of an open flame. Due to this unusual trait, chemists call the product of this chemical reaction “cold light.” To get more color variations, dyes that stimulate the luminol fluorescence are added to the liquids. After activation, the chemicals and dyes in the glow stick gradually react and a ubiquitous light glows for several hours until the reaction is over. Current scientific knowledge of chemiluminescence only allows for a single use of each glow stick.
Interesting Facts About Glow Sticks
An effect similar to chemiluminescence can be found in many organisms in nature. The organic light produced by these organisms is called bioluminescence. As an example, the firefly uses cells that contain a chemical called luciferin to make an enzyme called luciferase, which produces a charming light. And although fireflies are commonplace for many people, bioluminescence is more often seen in deep-sea creatures, such as certain jellyfish or the famous lantern fish. Similar to chemiluminescence, bioluminescence does not produce heat, only light.