2,890 km

The temperature of the mantle varies greatly, from 1000° Celsius (1832° Fahrenheit) near its boundary with the crust, to 3700° Celsius (6692° Fahrenheit) near its boundary with the core. In the mantle, heat and pressure generally increase with depth.

Humans have been to the moon and explored almost every corner of the planet – but there’s one place they have never been. An international group of scientists say they plan to be the first group to drill successfully into the Earth’s mantle, the planet’s interior, which lies just beneath the outer crust.

about 25 miles

5 to 50 kilometers

To make things more difficult, as they drill deeper into the Earth, they’ll encounter extreme temperatures, possibly in excess of 1,000 degrees Fahrenheit (538 degrees Celsius), and fantastic amounts of pressure — as much as 4 million pounds per square foot in the vicinity of the mantle.

THE deepest hole on Earth drops 40,000 feet below the surface and was part of an abandoned Soviet experiment. But the Kola Superdeep Borehole is just one of the world’s deepest darkest pits — many of which have a sinister history of swallowing people up.

So, why is the Great Blue Hole so dangerous? The Great Blue Hole of Belize is dangerous for three reasons: the inexperienced divers, water clarity, and the presence of sharks. Those three elements can alter the mindset of the divers and push them to make bad decisions while scuba diving.

It’s true that there are plenty of deep holes that exist, but none are truly bottomless. In reality, even the deepest ones have never penetrated all the way down below the Earth’s crust. To get something deeper, we’ll have to use our imagination.

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