British scientists have discovered the world’s deepest known undersea volcanic vents, known as “black smokers”, 3.1 miles (5000 meters) down in the Cayman Trough in the Caribbean. The vents consisted of rainbow-hued spires of copper and iron ores, erupting water hot enough to melt lead. The pressure at this depth – 500 times normal atmospheric pressure – is equivalent to the weight of a large family car pushing down on every square inch of ocean floor. This high pressure prevents the super heated water from boiling.
Deep-sea vents are undersea springs where geothermally superheated water erupts from the ocean floor. They were first seen in the Pacific three decades ago. Scientists are fascinated by deep-sea vents because the scalding water that gushes from them nourishes lush colonies of deep-sea creatures fueled by chemicals dissolved in the water. One of these chemicals, hydrogen sulfide, is highly toxic to most known organisms.
Life has traditionally been seen as driven by energy from the sun, but discovery of the biological communities supported by these deep-sea vents has forced scientists to rethink the rules of biology. Studying the life forms that survive under such bizarre conditions is providing insights into patterns of marine life around the world, how life on earth began, and even the possibility of life on other planets. Active hydrothermal vents are believed to exist on Jupiter’s moon Europa and ancient hydrothermal vents have been speculated to exist on Mars.