Sky lanterns are airborne paper lanterns traditionally found in some Asian cultures. They are constructed from oiled rice paper on a bamboo frame, and contain a small candle or fuel cell composed of a waxy flammable material. When lit, the flame heats the air inside the lantern, thus lowering its density causing the lantern to rise into the air. The sky lantern is only airborne for as long as the flame stays alight, after which the lantern floats back to the ground.
Sky lanterns are also referred to as sky candles or fire balloons, however this term is also used to refer to balloon munitions used during World War II.
In ancient China, sky lantern were strategically used in wars. However later on, non-military applications were employed as they became popular with children at carnivals. These lanterns were subsequently incorporated into festivals like the Chinese Mid-Autumn and Lantern Festivals. Pingsi in the Taipei County of Taiwan holds an annual Lantern Festival in which sky lanterns are released.