The Naga fireballs (also known as the Mekong lights, and “bung fai paya nak” by the locals, is a phenomenon with unconfirmed source said to be often seen in Thailand’s Mekong river, which is also seen in (Nong Khai province in Isan) and in Laos (Vientiane Province) in which glowing balls are alleged to naturally rise from the water high into the air. The balls are said to be reddish and to have diverse sizes from smaller sparkles up to the size of basketballs; they quickly rise up to a couple of hundred metres before disappearing. The number of fireballs reported varies between tens and thousands per night.
In contrast to the legend and lack of objective analysis of the Naga fireballs, a similar phenomenon in plasma physics is a free-floating plasma orb, which is created when surface electricity (e.g. from a capacitor) is discharged into a solution. Skeptic Brian Dunning writes that whatever is sailing through the air has mass, and “must have been physically propelled”. It would be impossible for anyone across the half-mile river to hear a gunshot because it would take 2.5 seconds for the sound to travel to the spectators, and by then the crowd watching has already noticed the light, drowning out the sound when it would reach them. There is no science that can explain “the Naga Fireballs to be naturally produced burning gas bubbles.