Deepest Point Is 36,000 Feet

The staggering depth of the Challenger Deep is a direct result of powerful geological forces. Located in the southern end of the Mariana Trench, this point is part of a subduction zone, where the massive Pacific Plate is slowly sliding beneath the smaller Mariana Plate. This tectonic collision carves an immense scar into the seafloor, creating the deepest known chasm on our planet. The environment at the bottom is one of extremes: perpetual darkness, near-freezing temperatures, and a water pressure over 1,000 times greater than at the surface, equivalent to the weight of 50 jumbo jets pressing down on a single person.

Reaching this remote and hostile (Review) world is an incredible feat of engineering. The first to make the journey were Swiss oceanographer Jacques Piccard and U.S. Navy Lieutenant Don Walsh, who descended in the bathyscaphe Trieste in 1960. For more than half a century, they remained the only humans to have witnessed the bottom firsthand. In recent years, a handful of other explorers and scientists have made the descent, yet the number of people who have visited the Challenger Deep is still smaller than the number who have walked on the moon. The sheer scale of the trench is difficult to fathom; even the world's tallest mountain, Mount Everest, would be swallowed by the depths, its peak remaining more than a mile beneath the waves.