About 71 percent of the Earth's surface is water-covered. More than eighty percent of our ocean is unmapped, unobserved, and unexplored, yet our technology keeps improving and were able to explore more of Earths oceans.
At approximately 3300 feet (1005 m), no light is able to penetrate the ocean water. Unlike the Twilight Zone which may appear pitch black to the naked eye, the Midnight Zone (Bathypelagic Zone) truly is a lightless universe. All the water above creates tremendous pressures, up to 5,800 pounds per square inch (680 kg per square cm). The pressure’s so great it’s hard to imagine any life other than bacteria could survive here. Yet it does. Many of the animals here are soft-bodied, which allows them to absorb pressures which might injure or kill other species. Like the animals of the Twilight Zone above, these creatures often survive by eating organic material which drifts down through the depths. Others actually feed off the earth itself, consuming bacteria produced from the methane and sulfides seeping through the ocean floor. The are one of the few food webs on the planet which do not include the sun. It’s only been recently that scientists discovered complex biological communities living around hydrothermal vents, deep underwater fissures which spew normally lethal substances like liquid carbon dioxide and sulfur. As strange as it seems, life has adapted to benefit from these chemicals, using them as a primary energy source in a place sunlight will never reach.