More specifically referred to as Naga Fireballs, these lights are seen along the Mekong River in Laos and Thailand. They are basketball-sized red fireballs seem to rise silently up from the water, shooting into the air about 100 meters and vanishing. They seem to occur every year around late October and range from thirty to as many as a few thousand! They are revered in Thailand as part of the Buddhist Lenten season.

Every year, Wan Ok Phansa, the final day of the season celebration, huge groups of people line up the bank of the river to watch in hopes of seeing the fireballs rise up from the water. The celebration commemorates the return of Buddha in Naga form, and it is widely believed by some Buddhists that the fireballs are actually the breath of the Naga, a giant sea serpent that awakes every year in honor of the Buddhist Lent. Photos such as these have been taken for years and scientists have many theories on what they depict, but no definitive proof.

Some researchers claim it must be phosphine gas being released from the river bottom, others say it is methane. But either of those would require highly specific environmental conditions and precise concentrations to produce the fireballs. Many scientists just don’t believe that type of precision could be counted on to occur every year in October, at the same place, year after year. There are British reports of the fireballs from the 1960s, and supposedly there are writings in Buddhist temples of the lights occurring long ago. In recent times, the lights have resulted in a boost in tourism as they are fun to watch; even though no one really knows just what it is they are seeing.