Great balls of fire

Every year, on the last night of the Buddhist retreat, something extraordinary takes place in the remote countryside of Nong Khai province in Thailand's northeast. The Mekong River, usually known for its murky water and large fish, suddenly starts throwing glowing balls of light high into the sky. Folk lore has it that the serpents - or naga in Thai - are shooting a series of pike balls from the bed of Mekong, marking and celebrating Lord Buddha's return from his retreat in heaven. Scientists shake their heads at this explanation, and blame gas combustion for the naga fireballs, which is less romantic but still hard to understand. So what is it out there? A paranormal moment, a natural phenomenon or perhaps even a hoax? The mysterious naga fireballs are expect to return to the Mekong on October 30, the night before the Halloween, and you can join the curious crowds and come up with your own answer. The place to go is Phon Phisai - a district on the outskirts of Nong Khai - where more than 100 fireballs shoot skywards every year. The phenomenon is as enigmatic as it is beautiful. Thousands of pink and red bursts of light rise from the Mekong. The glowing spheres, the size of chicken eggs, hang in the air for a few minutes before disappearing, leaving in their wake astonishment, mystification and many, many questions. Manas Kanoksil, a local doctor turned "myth-buster" in Nong Khai, has been observing and studying the fireballs for more than 10 years. The science that he's applied tells him that the bizarre phenomenon is the combustion of natural gases released from the riverbed and heat drifting on the surface. The combustion requires a complete set of perfectly natural occurrences, including the relative positions of the earth, sun and moon: hence its occurrence on the last night of the Buddhist Lent. However, the local people tend to be more interested in mythology than science, Way back at the birth of legends, the story goes, Nong Khai and other settlements along the Mekong were created by the water serpents called nagas. Only later was the saga imbued with Buddhist fancy: The Lord Buddha ascended to heaven for Lent to visit his mother, and his return during the full moon of the 11th lunar month was cause for rejoicing. To show their delight, the nagas shot fireballs into the air. The drama continues. A television crew once tried to convince witnesses that it was a hoax perpetrated by the Lao on the far side of the river. Unfortunately, the only proof was videotape of a few Lao firing their rifles into the air. A local artist living on the Thai bank, Manas Anuraksa, remains enchanted by the fireball phenomenon, regardless of the explanation. "It's very peculiar, and we're not sure who or what causes it, but whatever it is, I believe this mythical event could make Nong Khai special enough to become a wonder of the world." Manas is right. The sleepy little town, once known to visitors only as a place to get a cold beer before crossing the border to Laos, has become a popular destination thanks to the bizarre annual show. One way to watch the fireball is to rent a motorcycle and ride eastward along the Mekong from Muang district to Phon Phisai and Rattanawapee. Ask around about the best spots to stop - the riverbanks get quite crowded in places - and keep your eyes peeled from 6 to 9pm. The enigma has a spin-off as it always draws more than 300,000 visitors to Nong Khai. This year the locals are organising a six-night event to celebrate the Naga Fireball Festival, running from Saturday through November 1. Activities include an illuminated boat procession, singing contest, fireworks and cultural shows, all of which promise to add noise and colour to the nights.