It appears that gaping hole discovered deep in Siberia isn't the only one: Locals have encountered a second crater, smaller but otherwise almost exactly like the first. Local official Mikhail Lapsui told the Interfax-Ural news agency that reindeer herders in the Yamal region ("Yamal" means "End of the World" in the local tongue) found the second hole about 55 miles from the village of Antipayuta. "Inside the crater itself, snow can be seen," Lapsui is quoted as saying. No pictures or video of the second hole have been made available.

Scientists have visited the original hole, and although they haven't offered a specific explanation they did say there was "nothing mysterious" about the phenomenon. "It is simply Mother Nature's law with its internal pressure and changes in temperatures," researcher Andrey Plekhanov told the Siberian Times last week. The area is extremely rich in natural gas and the leading theory is that a pocket of the substance combined with water, salt and rising temperatures to produce a significant — but apparently not unique — eruption. The investigation team will likely want to examine the second hole for more data, but no expedition has been announced.

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That weird Siberian hole has a twin http://t.co/YRKiRSrkTF — Smithsonian Magazine (@SmithsonianMag) July 25, 2014

Scientists explore the inside of the mysterious Yamal sinkhole in Siberia http://t.co/Nykmz5rHJX pic.twitter.com/rZRBgzw5hm — Telegraph Pictures (@TelegraphPics) July 23, 2014

— Devin Coldewey, NBC News