A huge, mysterious crater spotted in remote Siberia has scientists scrambling for answers: Was it a meteor? Was it a weapon? Or was it an explosive sign of global warming?

The seemingly bottomless pit was spotted by an oil-and-gas industry helicopter flying over northern Siberia — a region notorious for devastating events.

It might be Armageddon, seeing as the place where it was found is known as Yamal, meaning “the end of the world.”

The most deadly meteor impact of modern times — the Tunguska air burst — happened in the region in 1908. It flattened vast swaths of forest over a 775-square-mile area.

No such streak in the sky, explosive flash or seismic event has been recorded recently.

But this mysterious hole has nevertheless appeared.

The Siberian Times reports that startled helicopter passengers talked their pilot into loitering over the mysterious crater. Engineer Konstantin Nikolaev then filmed the hole and uploaded the footage to YouTube.

They say the hole was big enough for their helicopter — a 60-foot-long Mi8 — to have comfortably entered without touching the sides.

Rumors and reality

Since the footage appeared online, the Internet has been abuzz with rumors of UFOs, secret entrances to the “hollow Earth” — as well as the more mundane weapon test sites and meteorite impact theories.

“We can definitely say that it is not a meteorite,” a spokesman for Russia’s Emergencies Ministry said.

Russian scientist Anna Kurchatova, from the Sub-Arctic Scientific Research Center, believes the cause is something more logical, such as global warming.

Siberia’s frozen soil — known as permafrost — contains millions of tons of methane gas. As the surface slowly warms, this gas begins to be released — and pools into highly volatile pockets.

A mixture of water, salt and gas may have ignited an underground explosion. Another possibility is that the gas pocket may simply have built up enough pressure to pop like a Champagne cork, she said.

Search for answers

Clues to the crater’s cause are not far away.

“A scientific team has been sent to investigate the hole and is due to arrive at the scene on Wednesday,” The Siberian Times reports.

The expedition includes experts from Russia’s Center for the Study of the Arctic, and the Cryosphere Institute of the Academy of Sciences.

They will sample the soil, water and air at the scene in order to determine the nature of the hole.

The crater was found in the Yamalo-Nenets Autonomous Region, some 25 miles from the Bovanenkovo gas field. The peninsula, which sticks into Arctic waters, is the source of Russia’s vast gas export market to Europe.