Question: what are the naga fireballs?
Answer: Naga fireballs (Thai: บั้งไฟพญานาค; RTGS: bang fai phaya nak), also known as bung fai phaya nak or "Mekong lights" and, formerly, "ghost lights" are a phenomenon said to be seen annually on the Mekong River. Glowing balls are alleged to naturally rise from the water high into the air.