The Challenger Deep is the deepest known point of the seabed of Earth,located in the western Pacific Ocean at the southern end of the Mariana Trench,in the ocean territory of the Federated States of Micronesia. According to the GEBCO Gazetteer of Undersea Feature Names the depression's depth is 10,920 ± 10 m (35,827 ± 33 ft) at 11°22.4′N142°35.5′E,although its exact geodetic location remains inconclusive and its depth has been measured at 10,902–10,929 m (35,768–35,856 ft) by deep-diving submersibles,remotely operated underwater vehicles,benthic landers,and sonar bathymetry. The differences in depth estimates and their geodetic positions are scientifically explainable by the difficulty of researching such deep locations.
The Mariana Trench is an oceanic trench located in the western Pacific Ocean,about 200 kilometres (124 mi) east of the Mariana Islands;it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about 2,550 km (1,580 mi) in length and 69 km (43 mi) in width. The maximum known depth is 10,984 ± 25 metres at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. The deepest point of the trench is more than 2 km (1.2 mi) farther from sea level than the peak of Mount Everest.
Don Walsh was an American oceanographer,U.S. Navy officer,and marine policy specialist. While aboard the bathyscaphe Trieste,he and Jacques Piccard made a record maximum descent in the Challenger Deep on January 23,1960,to 35,813 feet (10,916 m). Later and more accurate measurements have measured it at 35,798 feet (10,911 m).
Milwaukee Deep,also known as the Milwaukee Depth,is part of the Puerto Rico Trench. Together with the surrounding area,known as Brownson Deep,the Milwaukee Deep forms an elongated depression that constitutes the floor of the trench. As there is no geomorphological distinction between the two,it has been proposed that the use of both names to refer to distinct areas should be reviewed.
A deep-submergence vehicle (DSV) is a deep-diving crewed submersible that is self-propelled. Several navies operate vehicles that can be accurately described as DSVs. DSVs are commonly divided into two types:research DSVs,which are used for exploration and surveying,and DSRVs,which are intended to be used for rescuing the crew of a sunken navy submarine,clandestine (espionage) missions,or both. DSRVs are equipped with docking chambers to allow personnel ingress and egress via a manhole.
The Puerto Rico Trench is located on the boundary between the Caribbean Sea and the Atlantic Ocean. The oceanic trench,the deepest in the Atlantic,is associated with a complex transition between the Lesser Antilles subduction zone to the south and the major transform fault zone or plate boundary,which extends west between Cuba and Hispaniola through the Cayman Trough to the coast of Central America.
Kaikō was a remotely operated underwater vehicle (ROV) built by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for exploration of the deep sea. Kaikō was the second of only five vessels ever to reach the bottom of the Challenger Deep,as of 2019. Between 1995 and 2003,this 10.6 ton unmanned submersible conducted more than 250 dives,collecting 350 biological species,some of which could prove to be useful in medical and industrial applications. On 29 May 2003,Kaikō was lost at sea off the coast of Shikoku Island during Typhoon Chan-Hom,when a secondary cable connecting it to its launcher at the ocean surface broke.
The South Sandwich Trench is a deep arcuate trench in the South Atlantic Ocean lying 100 kilometres (62 mi) to the east of the South Sandwich Islands. It is the deepest trench of the Southern Atlantic Ocean,and the second-deepest of the Atlantic Ocean after the Puerto Rico Trench. Since the trench extends south of the 60th parallel south,it also contains the deepest point in the Southern Ocean.
Mir was a class of two self-propelled deep-submergence vehicles. The project was initially developed by the USSR Academy of Sciences along with Lazurit Central Design Bureau,and two vehicles were ordered from Finland. The Mir-1 and Mir-2,delivered in 1987,were designed and built by the Finnish company Rauma-Repola's Oceanics subsidiary. The project was carried out under the supervision of constructors and engineers of the Shirshov Institute of Oceanology.
USNS Indomitable (T-AGOS-7) was a United States Navy Stalwart-class ocean surveillance ship in service from 1985 to 2002. From 2003 until 18 June 2014,she was in commission in the National Oceanic and Atmospheric Administration (NOAA) as the oceanographic research ship NOAAS McArthur II. As of 2018 it serves as a mother ship now named the Deep Submersible Support Vessel (DSSV) Pressure Drop for the crewed deep-ocean research submersible DSV Limiting Factor.
Deep-sea exploration is the investigation of physical,chemical,and biological conditions on the ocean waters and sea bed beyond the continental shelf,for scientific or commercial purposes. Deep-sea exploration is an aspect of underwater exploration and is considered a relatively recent human activity compared to the other areas of geophysical research,as the deeper depths of the sea have been investigated only during comparatively recent years. The ocean depths still remain a largely unexplored part of the Earth,and form a relatively undiscovered domain.
The Molloy Deep is a bathymetric feature in the Fram Strait,within the Greenland Sea east of Greenland and about 160 km west of Svalbard. It is the location of the deepest point in the Arctic Ocean. The Molloy Deep,Molloy Hole,Molloy Fracture Zone,and Molloy Ridge were named after Arthur E. Molloy,a U.S. Navy research scientist who worked in the North Atlantic,North Pacific and Arctic Oceans in the 1950s-1970s.
The Sirena Deep,originally named the HMRG Deep,was discovered in 1997 by a team of scientists from Hawaii. Its directly measured depth of 10,714 m (35,151 ft) is third only to the Challenger Deep and Horizon Deep,currently the deepest known directly measured places in the ocean. It lies along the Mariana Trench,200 kilometers to the east of the Challenger Deep and 145 km south of Guam.
Calypso Deep is the deepest part of the Mediterranean Sea,located in the Hellenic Trench,Ionian Sea,62.6 km south-west of Pylos,Greece,with a maximum depth of 5,109 m (16,762 ft). It lies at about 36°34′N21°8′E.
Deepsea Challenger is a 7.3-metre (24 ft) deep-diving submersible designed to reach the bottom of the Challenger Deep,the deepest-known point on Earth. On 26 March 2012,Canadian film director James Cameron piloted the craft to accomplish this goal in the second crewed dive reaching the Challenger Deep. Built in Sydney,Australia,by the research and design company Acheron Project Pty Ltd,Deepsea Challenger includes scientific sampling equipment and high-definition 3-D cameras;it reached the ocean's deepest point after two hours and 36 minutes of descent from the surface.
DeepFlight Challenger is a one-person submersible built with the intention of reaching the Challenger Deep,utilizing DeepFlight technology from Hawkes Ocean Technologies. The submersible is owned by Virgin Oceanic.
Triton Submarines is an American company that designs and manufactures luxury submersibles for research,filming,deep-ocean exploration,and the superyacht and high-end tourism sectors.
Alan John Jamieson is a Scottish marine biologist,engineer,explorer and author,best known for his deep-sea exploration and study of life at the deepest places in the oceans. He is known for extensive use of deep-sea landers to establish the maximum depth and community dynamics of many organismal groups,as well as the discovery of many new species and highlighting the presence of anthropogenic impacts at full ocean depth. During the Five Deeps Expedition,and follow on expeditions in 2020,he completed various dives in a manned submersible to some of the deepest places in the world. He has published over 100 scientific papers and participated in 65 deep-sea expeditions.
Limiting Factor is a crewed deep-submergence vehicle (DSV) manufactured by Triton Submarines and owned and operated since 2022 by Gabe Newell’s Inkfish ocean-exploration research organization. It currently holds the records for the deepest crewed dives in all five oceans. Limiting Factor was commissioned by Victor Vescovo for $37 million and operated by his marine research organization,Caladan Oceanic,between 2018-2022. It is commercially certified by DNV for dives to full ocean depth,and is operated by a pilot,with facilities for an observer.
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