The Challenger Deep is the deepest known point in the Earth's sea floor hydrosphere, with a depth of 10,898 m (35,755 ft) to 10,916 m (35,814 ft) by direct measurement from submersibles, and slightly more by sonar bathymetry (see below). It is in the Pacific Ocean, at the southern end of the Mariana Trench near the Mariana Islands group. The Challenger Deep is a relatively small slot-shaped depression in the bottom of a considerably larger crescent-shaped oceanic trench, which itself is an unusually deep feature in the ocean floor. Its bottom is about 11 km (7 mi) long and 1.6 km (1 mi) wide, with gently sloping sides. The closest land to the Challenger Deep is Fais Island (one of the outer islands of Yap), 287 km (178 mi) southwest, and Guam, 304 km (189 mi) to the northeast. It is located in the ocean territory of the Federated States of Micronesia, 1 mi (1.6 km) from its border with ocean territory associated with Guam.
The depression is named after the British Royal Navy survey ship HMS Challenger, whose expedition of 1872–1876 made the first recordings of its depth. According to the August 2011 version of the GEBCO Gazetteer of Undersea Feature Names, the location and depth of the Challenger Deep are 11°22.4′N 142°35.5′E / 11.3733°N 142.5917°E / 11.3733; 142.5917 and 10,920 m (35,827 ft) ±10 m (33 ft).
June 2009 sonar mapping of the Challenger Deep by the Simrad EM120 (sonar multibeam bathymetry system for 300–11,000 m deep water mapping) aboard the RV Kilo Moana indicated a depth of 10,971 metres (35,994 ft; 6.817 mi). The sonar system uses phase and amplitude bottom detection, with a precision of better than 0.2% of water depth; this is an error of about 22 metres (72 ft) at this depth. Further soundings made by the US Center for Coastal & Ocean Mapping in 2011 are in agreement with this figure, placing the deepest part of the Challenger Deep at 10,994 m (36,070 ft), with a vertical precision of approximately 40 m (130 ft).
Only four descents have ever been achieved. The first descent by any vehicle was by the manned bathyscaphe Trieste in 1960. This was followed by the unmanned ROVs Kaikō in 1995 and Nereus in 2009. In March 2012 a manned solo descent was made by the deep-submergence vehicle Deepsea Challenger. These expeditions measured very similar depths of 10,898 to 10,916 metres (35,755 to 35,814 ft).
Other articles related to "challenger deep, challenger, deep":
... May 1876) of the British Royal Navy survey ship HMS Challenger enabled scientists to draw maps, which provided a rough outline of certain major submarine terrain features, such as the edge of the ... Among the many discoveries of the Challenger expedition was the identification of the Challenger Deep ... The Challenger scientists made the first recordings of its depth on 23 March 1875 at station 225 ...
... assumed life was sparse in the deep ocean ... Sir Charles Thompson and colleagues aboard the Challenger expedition discovered many deep-sea creatures of widely varying types ... The first discovery of any deep-sea chemosynthetic community including higher animals was unexpectedly made at hydrothermal vents in the eastern Pacific Ocean during geological ...
... The Summary Report of the HMS Challenger expedition lists radiolaria from the two dredged samples taken when the Challenger Deep was first discovered ... At the bottom of the Challenger deep, the Nereus probe spotted one polychaete worm (a multi-legged predator) about an inch long ... shallower ocean trenches (> 7,000 m) and on the abyssal plain, the lifeforms discovered in the Challenger Deep possibly represent taxa distinct from those in shallower ...
... Kaikō reached a maximum depth of 10,911.4 meters at the Challenger Deep on 24 March 1995, during its initial sea trials ... In February 1996, Kaikō returned to Challenger Deep, this time collecting sediment and microorganisms from the seabed at a depth of 10,898 meters ... In May 1998, Kaikō returned again to Challenger Deep, this time collecting specimens of Hirondellea gigas ...
Famous quotes containing the word deep:
“There is a mountain in the distant West
That, sun-defying, in its deep ravines
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