Helicopter passengers, including engineer Konstantin Nikolaev, recently spotted a massive crater 80 meters (250 ft) in diameter in the Yamal peninsula in northern Siberia, coincidentally referred to as “the end of the world”. The hole was filmed and put on YouTube, drawing international attention and speculation about its origin. No one is quite sure how deep the hole is or how it got there, though representatives from the Russian Academy of Sciences, Emergencies Ministry, and other experts have been called to investigate what caused this huge anomaly.

After the video was shared, various explanations have been put forth about how the hole came to be, ranging from meteorites sparking a sinkhole to aliens taking core samples. Some believe that there are geological clues indicating that the hole has likely been there for about two years. Others feel the soil inside the hole has been darkened due to exposure to extreme heat. The video shows something falling down into the hole, though it isn’t clear if it is sand or water.

The Siberian Times reported a spokesperson for the Yamal branch of the Emergencies Ministry was able to offer a small bit of preliminary insight. “We can definitely say that it’s not a meteorite,” the spokesperson said. “No details yet.”

As of now, the most plausible scenario was proposed by Anna Kurchatova from Sub-Arctic Scientific Research Centre. According to the Siberian Times, Kurchatova believes the proximity to the largest gas field in Yamal contributed to the hole’s formation. Around 10,000 years ago, that region was all sea. Over time, sand, salt, and methane gas could have become trapped in ice as permafrost spread across the region. Global warming, which is causing the permafrost to melt, released the gas, causing the pressure to become too great and explode, like a cork.

If Kurchatova is correct, it could mean trouble for gas lines and other potential pockets of trapped gas and salt. Arctic regions have the highest increase in the rate of warming, and these increasing temperatures are causing more of the permafrost to melt than what has been previously observed in the area.

Of course, the explanation could end up being a bit more ordinary and could have been a normal sinkhole caused by soil movement from underground water sources. Scientists arrived at the hole today (Wednesday) and will collect samples the air, water, and soil from around the area. It is hoped that they will be able to determine the cause of the hole quickly.