If you have never seen a sky lantern, you are truly missing out. These elegant, graceful paper lanterns create a stunning picture as they gently float into the air. They have become a popular choice to celebrate weddings, birthdays, and other special events, as well as festivals around the world. Yet they seem to defy the law of gravity. Here is a look at how sky lanterns work.
History of Sky Lanterns
Some historians believe that sky lanterns were tested by the Chinese military as far back as the third century BC, but their invention is usually attributed to Chinese military strategist Zhuge Liang, or Kongming, who lived from 181-234 AD.
As the story goes, Kongming was surrounded by enemy troops when he had the idea to fashion a tiny balloon from paper and write a message on it explaining his predicament. Thanks to his balloon, Kongming was rescued. Today, the traditional Chinese name for sky lanterns is Kongming lanterns.
Exactly how these paper lanterns made the jump from military applications to celebrations is clouded by the mists of time, but it is known that they quickly became a part of large festivals across Asia. By the beginning of the 16th century, they had become extraordinarily popular in Portugal and Brazil as well.
Today, sky lanterns are popular around the globe as a festive way to celebrate nearly any event. Huge launches of multiple lanterns can be seen at festivals and community gatherings, while backyard launches form an important part of many private celebrations.
Sky Lantern Materials
Traditional Asian sky lanterns are made of oiled rice paper attached to a bamboo frame. In Latin America, traditional sky lanterns are made from very thin, translucent paper colloquially known as silk paper, and mounted on a bamboo or wire frame.
Today, the sky is literally the limit, as new high-tech materials meet traditional construction methods to offer a vast array of colors, sizes, and designs. Regardless of the outer materials, however, each sky lantern is powered by a candle or a small wax fuel cell.
Physics Principles
Sky lanterns are, at their heart, miniature hot air balloons, and they operate on exactly the same principles of physics. Warm air rises because it is less dense than cold air, which translates into a lower mass per unit volume. One cubic foot of air at room temperature weighs approximately 28 grams, or one ounce. When heated by 100 degrees Fahrenheit, it weighs roughly 7 grams less.
The candle heats up the air inside the sky lantern, which is carefully crafted to provide only a small opening at the bottom for air to escape. The heated air creates forces known as lift, which causes the lantern to rise, and buoyancy, which keeps it suspended. When the candle or wax fuel cell burns out, the lantern returns gently to the earth.
Sky Lantern Dangers
There are some dangers associated with traditional sky lanterns. The primary concern is that the paper lantern could catch fire if it is tilted by wind or collision with an object. Although the paper itself would burn out in just a few seconds, it is possible that the fuel source could hit the ground while still burning. In fact, a huge fire occurred in the West Midlands of England in 2013 when a still-burning sky lantern landed at a plastics recycling plant.
Another possible danger is the wire frame used in many sky lanterns. It is not bio-degradable, and could pose a swallowing risk to local wildlife.
Many sky lantern manufacturers now address these risks, choosing flame-retardant lantern materials and replacing the wire with a bio-degradable rope frame alternative. Always choose sky lanterns from a trusted source with a good reputation to be sure that they meet the latest safety standards.
Also check your state and local laws. Due to fire risks, some locations have banned sky lanterns altogether. If your state and municipality allow them, though, and you choose lanterns that are designed for safety, sky lanterns provide a stunning backdrop for any evening celebration!
At Dynamite Fireworks, we don’t only sell top-quality, name-brand fireworks. We also provide the information you need to know to use them responsibly, legally, and safely. If you have any questions or concerns, give us a call at (219) 937-4090. We look forward to becoming your one-stop shop for all your fireworks needs!
