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Mariana Trench


Imagine the deepest, darkest place on Earth—an underwater trench plummeting to a depth of 35,800 feet, nearly seven miles below the ocean surface. The Mariana Trench is one of the least explored places on Earth. Deep enough to swallow Mt. Everest, the Mariana Trench was first pinpointed in 1951 by the British Survey ship Challenger II. Known since as Challenger Deep, it was not visited for nearly ten years. Jacques Piccard and Don Walsh descended in a submersible called the Trieste, which could withstand over 16,000 pounds of pressure per square inch. Their descent to the bottom in cramped quarters took five hours, but provided our first glimpses of the seafloor and life at the ocean’s greatest depths. The Mariana Trench represents just one small part of the Earth’s last, great frontier. Less than five percent of the entire ocean has been explored, yet scientists have found that even the deep sea has great numbers of species—and the discoveries have only just begun.



Ecological Uniqueness
Exploration and Research
Oceanographic and Bathymetric Features



The Mariana Trench
The Deepest Place in the Ocean
Ocean Explorer Voyage: Mariana Arc
Challenger Deep on Wikipedia



Mariana Trench Flythrough




The submersible Alvin. Photo:USGS

Walsh and Piccard in the bathyscaphe Trieste. Photo: NOAA

Deep sea anglerfish