The pilot and co-pilot of a Boeing 747-8 flying from Hong Kong to Anchorage, Alaska, were passing near the Russian peninsula of Kamchatka when they observed a fiery reddish glow over the Pacific. With no other planes in the area at the time to confirm the sighting, they took pictures of and reported to Air Traffic Control, then completed the flight to Anchorage. So … what was it?

On August 24, 2014, Dutch pilot and photographer JPC van Heijst was five hours into the ten hour flight when he spotted a single intense bolt of light shoot vertically into the air. There were no other flashes or storms in the area or on their radar. Twenty minutes later, he saw the red glow. Having heard reports of earthquakes in California, Chile and Iceland, he checked for quakes or volcanic activity on the route but saw no alerts. Despite that, van Heijst later wrote on pbase.com that he suspected it was an underwater volcano.

The closer we got, the more intense the glow became, illuminating the clouds and sky below us in a scary orange glow, in a part of the world where there was supposed to be nothing but water. The only cause of this red glow that we could think of, was the explosion of a huge volcano just underneath the surface of the ocean, about 30 minutes before we overflew that exact position.”

Sounds plausible, although van Heijst saw no ash plume as they continued to Alaska. Because of that, some experts suspected it was the LED lights used by fishing boats like the green glow that astronaut Reid Wiseman saw recently off the coast of Bangkok. However, the intensity of the light seen by van Heijst would have required at least 50 boats and none were reported in the area.

Another theory was light pollution from a city, but the sighting was far from any coastal or island cities capable of producing that kind of glow. Investigators are now searching the area for signs of an active volcano or a new island formed by one.

Volcano? Boats? Methane gas bubbling under the ocean? Or was it something else?