Scientists have finally descended into one of the three enormous holes that mysteriously opened up in Siberia several months ago.

The holes, on Russia’s Yamal Pensinsula, captured attention after one was first spotted by an aircraft pilot in July, who took this pic:

Picture: The Siberian Times

The world went mad. Suspected causes ranged from meteorites to underground explosions to extra-terrestrial.

Now a team from the Russian Centre of Arctic Exploration has climbed down to the bottom of the largest hole, about 16m, to stand on a frozen lake which itself is about another 10.5m deep.

The team had to brave winter temperatures of -11C, as the crater was a mudbath in summer with water pouring into it from the ground above.

Vladimir Pushkarev, director of the Russian Centre of Arctic Exploration, took a few amazing snaps of the expedition.

Picture: Vladimir Pushkarev/Russian Centre of Arctic Exploration

The team is following a theory that the holes might have been caused by underground gas explosions.

“We took all the probes we planned, and made measurements,” Pushkarev told The Siberian Times.

“Now scientists need time to process all the data and only then can they draw conclusions.”

Picture: Vladimir Pushkarev/Russian Centre of Arctic Exploration

The centre believes it’s possible the holes didn’t “open up” in July and perhaps simply hadn’t been noticed before.

“We plan to explore the surrounding area, comparing images from space, and even those taken in the 1980s, to understand if there are – or were – some similar objects,” Pushkarev said.

Picture: Vladimir Pushkarev/Russian Centre of Arctic Exploration

One unusual thing the team noticed was the largest hole is located on the intersection of two tectonic faults.

While the peninsula itself is relatively quiet in a seismological sense, the temperature beneath the hole was “higher than usual”.

There’s more pics and details about the Yamal hole expedition here at The Siberian Times

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