The Naga fireballs of the Mekong river are not a question of If, but a question of What. They are one of the most well documented unexplained phenomena in the entire world. Every year during October on the night of Wan Awk Pansa thousands of spectators gather on the banks of the Mekong river in Thailand and Laos to see the legendary Naga breathe forth balls of fire from the river itself. Many have been watching this every year for their entire life. The balls themselves are reddish in color and are about the size of an egg. They slowly and silently rise from the river before accelerating high into the air where they disappear. There can be anywhere from tens to thousands of these glowing orbs per night. The balls themselves are seen either side of the festival night, which attests to the fact its more than likely of natural origin rather than an organized display by officials.

Their supernatural origin is not without opposition. Manas Kanoksin, a doctor from Nong Khai strongly believes that fermenting sediment on the rivers bottom causes pockets of methane gas to form, and that the Earths position in relation to the sun during those days of the year causes them to rise, then spontaneously ignite in the presence of ionized oxygen. Italian chemists Luigi Garlaschelli and Paolo Boschetti, have replicated the lights by adding chemicals to the gases formed by rotting compounds. But other researchers dismiss this theory, pointing out that the rocky river bottom doesnt have much sediment, and that the waters turbulence would break up any such methane bubbles before they reached the waters surface. Whatever the cause, the Naga fireballs of the Mekong are one of the least known, most spectacular of phenomena to observe.

Each year, hundreds of fireballs spontaneously explode out of Thailands Mekong River. Known as bung fai paya nak or Naga fireballs, they have appeared on the late autumn night of the full moon at the end of the Buddhist Lent for as long as anyone can remember, according to a 2002 Time magazine story about the phenomenon. Some believe the balls come from the breath of Naga, a mythical serpent that haunts the river. (Locals use old grainy pictures and postcards of the mythical beast to prove its presence to tourists.) Others believe the fireballs are actually pockets of methane bubbling up from the river, but many locals remain convinced that the fireballs are of a supernatural origin.

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