|
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 four vessels ever to reach the bottom of the Challenger Deep, as of 2010. Between 1995 and 2003, this 10.6 ton unmanned submersible conducted more than 250 dives, collecting 350 biological species (including 180 different bacteria), 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.〔 Another ROV, ''Kaikō7000II'', served as the replacement for ''Kaikō'' until 2007. At that time, JAMSTEC researchers began sea trials for the permanent replacement ROV, ''ABISMO'' (Automatic Bottom Inspection and Sampling Mobile). ''ABISMO'' is currently one of only three ROVs rated to 11,000-meters (the other two being ''Nereus'', built and operated by the Woods Hole Oceanographic Institution, and ''Deepsea Challenger'', piloted by director James Cameron). ==Challenger Deep== (詳細はBathymetric data obtained during the course of the expedition (December 1872 – 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 continental shelves and the Mid-Atlantic Ridge. This discontinuous set of data points was obtained by the simple technique of taking soundings by lowering long lines from the ship to the seabed. Among the many discoveries of the ''Challenger'' expedition was the identification of the Challenger Deep. This depression, located at the southern end of the Mariana Trench near the Mariana Islands group, is the deepest surveyed point of the World Ocean. The ''Challenger'' scientists made the first recordings of its depth on 23 March 1875 at (station 225 ). The reported depth was 4,475 fathoms (8184 meters) based on two separate soundings. On 23 January 1960, Don Walsh and Jacques Piccard were the first men to descend to the bottom of the Challenger Deep in the ''Trieste'' bathyscaphe. Though the initial report claimed the bathyscaphe had attained a depth of 37,800 feet, the maximum recorded depth was later calculated to be . At this depth, the water column above exerts a barometric pressure of , over one thousand times the standard atmospheric pressure at sea level. However, even at this great depth and pressure, a small flounder-like fish was seen moving away from the spotlight of the bathyscaphe. Since then, only one manned vessel has ever returned to the Challenger Deep, the Deepsea Challenger, which was piloted by director James Cameron on March 26, 2012 to the bottom of the trench. In March 1995, ''Kaikō'' became the second vessel ever to reach the bottom of the Challenger Deep, and the first craft to visit this location since the ''Trieste'' mission.〔〔 The maximum depth measured on that dive was 10,911.4 meters, marking the deepest dive for an unmanned submersible to date. On 31 May 2009, ''Nereus'' became the third vessel to visit the bottom of the Challenger Deep, reaching a maximum recorded depth of 10,902 meters.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kaikō」の詳細全文を読む スポンサード リンク
|