Challenger Deep

The Challenger Deep is a relatively small slot-like depression at the bottom of a sizable crescent-shaped trench, itself an unusually deep seafloor feature. Challenger Deep consists of three basins, each 6–10 km (3.7–6.2 mi) long, 2 km (1.2 mi) wide, and over 10,850 m (35,597 ft) deep, tiered from west to east. hills 200–300 m (656–984 ft) high between basins, arranged in a pattern. The three basins extend approximately 48 km (30 miles) from west to east, measured at equal depths of 10,650 m (34,941 ft). Both the western and eastern basins record depths (according to sonar soundings) in excess of 10,920 m (35,827 ft), while the central basin is slightly shallower. The closest land masses to Challenger Deep are Fais Island (one of Yap's outer islands), 287 kilometers (178 miles) southwest, and Guam, 304 kilometers (189 miles) northeast. Detailed sonar mapping of the western, central, and eastern basins combined with DSSV pressure drop and manned drop in June 2020 reveals them undulating with slopes and rock piles over layers of pelagic ooze became. This is consistent with the description that the Challenger Deep consists of elongated seafloor segments with distinct subbasins or sediment-filled pools.

Over the years, many different vessels have been involved in the search and survey of the deepest locations in the world's oceans, and continue into the 21st century. The accuracy of determining geographic position and the beamwidth of multibeam) echo sounder systems limit the horizontal and vertical bathymetric resolution that hydrographers can obtain from field data. This is especially important when sounding in deep water, as the footprint of the acoustic pulse grows as it reaches the distant seafloor. In addition, sonar operation is affected by changes in the speed of sound, especially in the vertical plane. Velocity is determined by the bulk modulus, mass, and density of water. Bulk modulus is affected by temperature, pressure, and dissolved impurities (usually salt).

In 1875, while sailing from the Admiralty Islands of the Bismarck Islands to Yokohama, Japan, the three-masted sailing corvette Challenger attempted to land in the Spanish Mariana Islands (now Guam), but was blown away by an "inexplicable wind". leaned to Prevent them from "visiting the Carolines or the Radrones". Their altered path crossed an undersea canyon that later became known as Challenger Deep. Depth soundings were made by Bailey-weighted marked ropes and geographic positions were determined by celestial navigation (with an estimated accuracy of 2 nautical miles). One of their samples was taken within 15 miles of the deepest point in all of Earth's oceans. On March 23, 1875, HMS Challenger, at sample station #225, made a 11 degree 24 degree sound on the ocean floor (the deepest sound on Earth's eastward voyage in over three years) at a depth of 4,475 fathoms (26,850 feet, 8,184 m). recorded in 143 degrees 16 minutes north latitude east longitude – Confirmed with a second sound at the same location. The serendipitous discovery of the Earth's deepest depression by the first-ever large-scale scientific expedition devoted to the emerging science of oceanography was incredibly fortunate, making it the third deepest place on Earth (only 150 miles east of Challenger). This is particularly noteworthy when compared to the Sirena Deep (at nautical miles). Deep), which remained undiscovered for the next 122 years.

Seventy-five years later, the 1,140-ton British survey vessel HMS Challenger II surveyed the deepest depths southwest of Guam reported in 1875 by its predecessor, HMS Challenger, during its three-year circumnavigation westward. Challenger 2, on its southbound voyage from Japan to New Zealand (May–July 1951), conducted surveys of the Mariana Trench between Guam and the Ulithi Atoll using seismic-scale bomb soundings, measuring the maximum depth. 5,663 fathoms (33,978 feet, May to July 1951). 10,356 meters). That depth exceeded the verification capabilities of the Challenger II's echo sounders, so they resorted to using a wire strung with "140 pounds of scrap iron" to reach a depth of 5,899 fathoms (35,394 ft; 10,788 m). was recorded. Dr. Thomas F. Gaskell, senior scientist on board Challenger II, recalled: It took from 10:00 to 5:00 to 20:00 to 7:00 in the evening, or an hour and a half, before the iron weight fell into the sea. -under. It was nearly dark by the time the weights were lifted, but the readings were filled with excitement...In New Zealand, the Challenger II team, with the support of Royal New Zealand Shipyards, "boosted the echo sounders and Successfully made a record "maximum depth". They returned to the "Mariana Deep Sea" (sic) in October 1951. Using a new and improved echo sounder, they drew a survey line perpendicular to the trench's axis and discovered "a region of considerable depth exceeding 5,900 fathoms (35,400 fathoms)." ft; 10,790 m)” – later identified as the western basin of Challenger Deep. The maximum recorded depth was 5,940 fathoms (35,640 feet, 10,863 m) at 11°19'N, 142°15'E. A navigation accuracy of several hundred meters was achieved by celestial navigation and LORAN-A. The term 'Challenger Deep' came into use after this 1951-1952 Challenger circumnavigation to commemorate the two British ships of the same name that were responsible for discovering the deepest basin in the world's oceans. Note that

In August 1957, the 3,248-tonne Vernadsky Geochemical Institute research vessel Vityaz landed in the western basin of the Challenger Deep at 11°20.9'N, 142°11.5'E to a maximum depth of 11,034 ± 50 m (36,201 ± 164 ft). was recorded. Travel the area with ease on Cruise 25. She returned in 1958 on Cruise 27 and conducted a detailed single-beam bathymetric survey including more than 10 deep transects, extensively surveying the Western Basin and glimpsing the Eastern Basin. Fisher recorded a total of three Vityaz bathymetric stations in Figure 2, "The Trench" (1963), one within yards of 142°11.5'E, and a third at 11°20.0'N, 142'E. It's at degrees 07 minutes and all 11,034. Depth ± 50 m (36,201 ± 164 ft). This depth is considered a statistical outlier, with no proven depth greater than 11,000 m. Taira found that when the Vityaz depth was corrected by the same method used in the Japanese RV Hakuho Maru expedition of December 1992, it was 10,983 ± 50 m, in contrast to modern depths by the multibeam echo sounding system. m (36,033 ± 164 ft). Over 10,900 meters (35,800 ft), NOAA allows a maximum of 10,995 ± 10 m (36,073 ± 33 ft) in the Western Basin.

The first definitive verification of both the depth and location of the Challenger Deep (Western Basin) was determined by Dr. R.L. Fisher of the Scripps Institution of Oceanography aboard the 325-ton research vessel Stranger. They used the explosion sound and in July 1959 he recorded 10,850 ± 20 m (35,597 ± 66 ft) at around 11°18'N 142°14'E. Stranger used astronomical satellites and LORAN-C for navigation. LORAN-C navigation provided a geographic accuracy of over 460 m (1,509 ft). According to another source, RV Stranger used bomb acoustics to survey a maximum depth of 10,915 ± 10 m (35,810 ± 33 ft) at 11°20.0'N, 142°11.8'E. Differences between the geographic position (latitude/longitude) of the Stranger's innermost depths and that of previous expeditions (Challenger II 1951, Vityaz 1957 and 1958) "probably contributed to the difficulty in fixing the ship's position. by certainty.” Stranger's north-south zigzag survey passed well east of the East Basin on the southward side, and passed well west of the East Basin on the northward side, so he was unable to find the East Basin of Challenger Deep. The maximum depth measured near 142°30'E was 10,760 ± 20 m (35,302 ± 66 ft), approximately 10 km west of the deepest point of the eastern basin. This was an important information gap, as the eastern basin was later reported to be deeper than the other two basins. Stranger crossed the Central Basin twice, measuring a maximum depth of 10,830 ± 20 meters (35,531 ± 66 feet) near 142°22'E. A depth of 10,805 ± 20 m (35,449 ± 66 ft) was recorded at the western edge of the central basin (about 142°18'E). The western basin has been subjected to four transects by The Stranger and has a recorded depth of 10,830 ± 20 m (35,531 ± 66 ft) towards the central basin, where the Trieste dived in 1960 (11°N). 18.5 minutes near 142 degrees 15.5 minutes east longitude and where Challenger II was hidden). , in 1950, recorded 10,863 ± 35 m (35,640 ± 115 ft). At the westernmost point of the West Basin (about 142°11'E), Stranger recorded 10,850 ± 20 m (35,597 ± 66 ft). One kilometer south of where Vityaz recorded a depth of 11,034 ± 50 m (36,201 ± 164 ft) in 1957–1958, Fisher said: Functions used". After surveying Challenger Deep, the Stranger proceeded to the Philippine Trench, crossing the trench more than 20 times in August 1959, discovering a maximum depth of 10,030 ± 10 m (32,907 ± 33 ft), indicating that the Challenger Trench is approximately 800 m deep. established to be Deeper than the Philippine Trench (2,600 feet). Stranger's 1959 survey of Challenger Deep and the Philippine Trench informed the US Navy of suitable locations for Trieste's record dive in 1960.

For the second leg of the Proa expedition, Fisher returned to Challenger Deep on April 12–13, 1962, aboard the Scripps research vessel Spencer F. Baird (formerly the large steel-hulled U.S. Army tug LT-581). A depth recorder (PDR) was used. ) validates the previously reported extreme depths. They recorded a maximum depth of 10,915 meters (35,810 feet) (location unknown). In addition, at Point "H-4" on Challenger Deep, the expedition made three taut wire soundings. On April 12, the first cast was made at 5,078 fathoms (corrected for wire angle), altitude 9,287 meters (30,469 feet), latitude 11°23. 142°19.5'N, Central Basin (Until 1965, US research vessels recorded bathymetry in fathoms). The second cast also reached over 5,000 fathoms on April 12 at 11 degrees 20.5 minutes north latitude and 142 degrees 22.5 minutes east longitude in the central basin. On April 13, the final cast recorded 5,297 fathoms (wire angle corrected) 9,687 meters (31,781 feet) at 11°17.5'N 142°11'E (west of the basin). They were chased by the hurricane just two days after they were on site. Once again Fisher completely missed the eastern basin of Challenger Deep, which was later found to be the deepest part.

On Leg 3 of Expedition 76010303 of the Hawaii Geophysical Institute (HIG), the 156-foot (48-meter) research vessel Kana Keoki, under Chief Scientist Donald M. Husson, explored primarily the Challenger Deep region. Departed from Guam for seismic research. The ship was equipped with an air gun (for seismic reflection surveys deep in the Earth's mantle), a magnetometer, a gravimeter, 3.5 kHz and 12 kHz sonar her transducers, and a precision bathymetric recorder. They ran the trench from east to west from March 13 to 15, 1976, collecting single-beam bathymetry, magnetic and gravitational measurements, and air guns along the trench's axis in the afterarc and I made it go deep into the forearc. Ontong Java Plateau. All three deep basins of Challenger Deep were covered, but Kana Keoki recorded a maximum depth of 7,800 m (25,591 ft). The seismic information obtained from this survey helped us understand the subduction of the Pacific plate under the Philippine Sea plate. In 1977, Kana Keoki returned to Challenger Deep to cover more of the forearc and backarc.

The Hydrographic Office of the Japan Coast Guard (JHOD) deployed the newly commissioned 2,600-ton survey vessel Takuyo (HL 02) to Challenger Deep from 17 to 19 February 1984. Takuyo was the first Japanese ship to be equipped with the new narrow beam SeaBeam. A multi-beam sonar echo sounder, it was the first survey vessel with multi-beam capabilities to survey the Challenger Deep. Because the system was so new, JHOD had to develop its own software to draw bathymetric maps based on SeaBeam digital data. In just three days, they tracked 500 miles of bathymetry and covered about 140 km2 of Challenger Deep with multibeam acoustic waves. Under the direction of Chief Scientist Hideo Nishida, they used CTD temperature and salinity data from the upper 4,500 meters (14,764 ft) of the water column to correct the depth readings, which were then used by the Scripps Institute of Oceanography (Fisher ) and in consultation with other GEBCO experts. their depth correction methodology. They combined NAVSAT, LORAN-C and OMEGA systems to achieve geodetic positioning with an accuracy of over 400 meters (1,300 feet). The deepest recorded location was 10,920 ± 10 meters (35,827 ± 33 feet) at 11°22.4'N 142°35.5'E. We recorded for the first time that the eastern basin was the deepest of the three stratified pools. In 1993, GEBCO accepted a reported depth of 10,920 ± 10 m (35,827 ± 33 ft) as the deepest depth of the world's oceans. Technological advances, such as improved multi-beam sonar, will power the future of unraveling the mysteries of the Challenger Deep.

Scripps' research vessel Thomas Washington returned to Challenger Deep in 1986 during Leg 8 of the Papatoua expedition and deployed one of the first commercial multi-beam echo sounders capable of reaching the deepest trenches: the 16-beam Seabeam. Equipped with Classic. This gave Chief Scientist Yayanos the opportunity to fly through the Challenger Deep using the most modern depth sounding equipment available. Just before midnight on April 21, 1986, a multibeam echo sounder mapped the ocean floor of Challenger Deep in a strip about eight to seven miles wide. The maximum recorded depth was 10,804 meters (35,446 feet) (depth location unknown). “My impression of this cruise comes from thinking about what revolutionary things Seabeam data can bring to deep biology,” said Mr. Yayanos.

On August 22, 1988, the U.S. Navy-owned 1,000-ton research vessel Moana Wave (AGOR-22) was launched by the Hawaii Geophysical Institute (HIG) at the University of Hawaii under the leadership of Chief Scientist Robert C. Tunell. was operated by The University of South Carolina passed northwest through the central basin of Challenger Deep and conducted single-beam bathymetry tracking by her 3.5 kHz narrow (30-degree) beam echo sounder equipped with a high-precision depth recorder. In addition to sonar bathymetry, 44 sediment gravity cores and 21 box cores were collected. The deepest recorded echo soundings ranged from 10,656 to 10,916 meters (34,961 to 35,814 feet), with maximum depths at 11°22'N, 142°25'E in the Central Basin. This was the first evidence that all three basins had depths greater than 10,900 meters (35,800 feet).

The 3,987-tonne Japanese research vessel Hakuho Maru, sponsored by the University of Tokyo Ocean Research Institute, sailed on cruise KH-92-5 with three Sea-Bird SBE-9 Ultra-Deep CTD (Conductivity-Temperature-Depth ) cast the profiler. The central CTD was located in the eastern basin at 11°22.78'N, 142°34.95'E, at 10,989 meters (36,053 ft) and altitude of 10,884 meters (35,709 ft) on the SeaBeam depth recorder. ft) by CTD. Two other CTDs were launched 19.9 km north and 16.1 km south. Hakuho Maru is equipped with a narrow-beam SeaBeam 500 multi-beam echo sounder for depth measurements and an automated navigation system with input from NAVSAT/NNSS, Doppler logs, EM logs, and track displays. and the geolocation accuracy approached 100. meters (330 feet). When conducting CTD operations at Challenger Depth, they used SeaBeam as a single-beam depth recorder. At 11°22.6'N 142°35.0'E the corrected depth was 10,989 m (36,053 ft) and at 11°22.0'N 142°34.0'E the depth was 10,927 m (35,850 ft). Both are in the eastern basin. This may indicate that the basin is not a flat sedimentary pond, but rather may be undulating by more than 50 meters (160 feet). Taira said, "We thought we detected a valley 5 meters (16 feet) deeper than the Vityaz record. There may be depths in excess of 11,000 meters (36,089 feet) on horizontal scales below the measured beam width. ', he said. SeaBeam's 2.7-degree beamwidth sonar pins each extend to cover a circular area approximately 500 meters (1,640 feet) in diameter at a depth of 11,000 meters (36,089 feet), thus reducing seafloor depressions smaller than that size. is difficult to detect from a sonar emitting platform seven miles up.

From most of 1995 to 1996, the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) used the 4,439-ton research vessel Yokosuka to test and inspect the remotely operated vehicle (ROV) Kaiko at an altitude of 11,000 meters. was carried out. ROV "Shinkai" with a total length of 6,500 meters. KAIKO was ready for the first full depth dive in February 1996 during Yokosuka Voyage Y96-06. In this cruise, JAMSTEC defined the Challenger Deep area (11°10'N to 11°30'N, 141°50'E to 143°00'E). It was later recognized that this area contained three separate pools/basins. JAMSTEC expeditions will focus their research on this stratum for the next 20 years. Yokosuka employed a 151-beam SeaBeam 2112 12 kHz multi-beam echo sounder, enabling a search zone 12-15 km wide at a depth of 11,000 meters (36,089 ft). The depth accuracy of the Yokosuka seabeam was about 0.1% of the depth (that is, ±110 meters (361 ft) at 11,000 meters (36,089 ft) depth). The ship's dual GPS system achieved geodetic positioning within two digits of meters (over 100 meters (328 feet)).

From January 11 to 13, 1998, Cruise KR98-01 dispatched JAMSTEC's two-year-old deep-sea research vessel RV Kairei (4,517 tons) to the south under Kantaro Fujioka, Senior Research Scientist, to explore the Challenger Deep. We also conducted a thorough in-depth investigation. Tracked primarily along the 070–250° trench axis, five 80km bathymetric tracks spaced approximately 15km apart were created and superimposed with SeaBeam 2112-004 (which allows the seafloor to penetrate to 75m below the seafloor). Exploration is now possible) ) At the same time, we will acquire gravitational and magnetic data covering the entire Challenger Deep (western, central and eastern basins). With both geophysical and biological goals, Kairei returned in May 1998 on the KR98-05 cruise with the ROV Kaikou under the command of Chief Scientist Jun Hashimoto. The bathymetric survey, conducted May 14-26, was the most intensive and thorough depth and seismic survey of the Challenger Deep ever conducted. Each night, KAIKO deployed about four hours of bottom time for bio-related sampling, plus about seven hours of vertical navigation time. While KAIKO was on board for maintenance, KAIREI conducted bathymetric surveys and observations. Kailey divided the study area into a grid of about 130 km north-south and about 110 km east-west. KAIKO made six dives (#71-75), all at the same location (11°20.8'N, 142°12.35'E) near the bottom contour of the West Basin at an elevation of 10,900 m (35,800 ft). Bathymetric maps of the region Data generated from data obtained in 1998 indicate that the maximum depths of the eastern, central, and western depressions are 10,922 ± 74 m (35,833 ± 243 ft), 10,898 ± 62 m (35,755 ± 203 ft), and 10,908 ± 36 m (1999). ) consists of three 'distinct right-stepped basins' bounded by the contour lines of ).The size of each deep sea is: approximately the same, length 14–20 km, and 4 km wide.” They conclude that “three separate strips of abyss constitute the 'Challenger Deep' and identify them as the eastern, central, and western abysses. It concluded with a proposal that the deep depth is 10,938 meters (35,886 ft)". The deep west (11°20.34'N, 142°13.20°E). The depth was "obtained during the mapping of the zonal and … It was found in both the north-south and east-west swaths.” Velocity of speech correction was from XBT to 1,800 m (5,900 ft) and CTD was less than 1,800 m (5,900 ft). According to the 1999 Kairei Cruise cross-track survey, the maximum depths of the eastern, central, and western depressions are 10,920 ± 10 m (35,827 ± 33 ft), 10,894 ± 14 m (35,741 ± 46 ft), and 10,907 ± 13 m (35,741 ± 46 ft). meter. In 2002, Kailey returned to Challenger Deep as cruise KR02-13 (Japan-US-Korea Joint Research Program) from October 16-25, 2002. Chief Scientist Jun Hashimoto, and again Kazuyoshi Hirata will oversee the ROV Kaidō team. The study narrowed the size of each of the three basins to be 6 to 10 km long, about 2 km wide, and over 10,850 m (35,597 ft) deep. In marked contrast to the ridge surveys of 1998 and 1999, a detailed survey in 2002 found that the deepest point of the Challenger Deep was located in the eastern basin near 11°22.260'N, 142°35.589'E, with a depth of was found to be 10,920 ±. 5 m (35,827 ± 16 ft) deep. It lies approximately 290 m (950 ft) southeast of the deepest point measured by the survey vessel Takuyo in 1984. Both the Western Basin and Eastern Basin surveys in 2002 were rigorous and cross-grid with particular care. Located in the eastern basin, it has 10 parallel tracks with a north-south and east-west spacing of less than 250 meters. On the morning of October 17, ROV Kaikō dive #272 began and was recovered over 33 hours, with the ROV at the bottom of the West Basin (11°20.148'N, 142°11.774°E, around 10,893m above sea level). worked for 26 hours. (35,738 feet)). Kaiko made five dives in the same area each day to prepare benthic landers and other scientific equipment, with dive 277 being recovered on October 25. Traps thrived on large numbers of amphipods (sea fish), and cameras recorded holoturians (sea cucumbers), white polychaetes (bristles), tubeworms, and other species. During the 1998 and 1999 expeditions, Kairei was equipped with a GPS satellite-based radio navigation system. The U.S. government ended the selective availability of GPS in 2000, so during the 2002 survey, Kairei had access to undegraded GPS location services and achieved single-digit meter accuracy in geodetic positioning.

The 2.516-tonne research vessel Melville, then operated by the Scripps Institution of Oceanography, participated in the Cook Expedition Sixth leg on February 10, 2001 with University of Hawaii Chief Scientist Patricia Fryer. On the same day, I left Guam for Challenger Deep and conducted a survey of the title. The "Southern Mariana Subduction Factory Study" includes HMR-1 sonar mapping, magnetics, gravimetry, and dredging of the Mariana Arc region. They covered all three basins and then followed a 120 nautical mile (222.2 km) long bathymetric line east to west, then north from Challenger Deep on a side road 12 km (7.5 mi) to the 90 nautical mile ( 166.7 km) covered. With overlapping bands from the SeaBeam 2000 12 kHz multi-beam echo sounder and MR1 towing system, proceed north towards the backarc. They also collected magnetic and gravitational information, but not seismic data. Their primary survey instrument is a shallow towed 11/12 kHz bathymetric sidescan sonar developed and operated by the Hawaii Mapping Research Group (HMRG), a research and operations group within the University of Hawaii Department of Marine and Geosciences. It was an MR1 towed sonar. Technology (SOEST) and Hawaii Geophysical and Planetary Institute (HIGP). The MR1 is fully ocean capable and provides both bathymetry and sidescan data. The seventh leg of the Cook expedition continued the MR-1 survey of the Mariana Trench back-arc from March 4 to April 12, 2001 under Oregon State University's Chief Scientist Sherman Bloomer.

In May-June 2009, the US Navy-owned 3,064-ton catamaran research vessel Kilomoana (T-AGOR 26) was dispatched to the Challenger Deep area for research. Kilomoana is crewed by a private crew and operated by SOEST. 2 multi-beam echo sounders (191 beam 12 kHz Kongsberg Simrad EM120 with SBP-1200, capable of 0.2-0.5% depth accuracy across all bands) with sub-bottom profiler add-on, gravimeter, magnetometer . The EM-120 uses a 1 x 1 degree sonar emission at sea level. Each 1-degree beamwidth sonar ping expands to cover a circular area approximately 192 meters (630 feet) in diameter at a depth of 11,000 meters (36,089 feet). During mapping of Challenger Deep, sonar instruments indicated a maximum depth of 10,971 m (35,994 ft) at an undisclosed location. Navigation equipment includes Applanix POS MV320 V4 with 0.5 to 2 m accuracy. RV Kilo Moana was also used as a support vessel for the Hybrid Remotely Operated Underwater Vehicle (HROV) Nereus, which made three dives to the bottom of Challenger Deep during its May-June 2009 cruise, although Sonar was the support vessel. The maximum depth set by could not be verified. .

Cruise YK09-08 returned JAMSTEC's 4,429-ton research vessel Yokosuka to the Mariana Trough and Challenger Deep in June and July 2009. Their assignment was her two-part program. This meant investigating three hydrothermal vent sites south of the Mariana Trough backarc basin. Using the autonomous underwater vehicle "Urashima", we navigated approximately 130 nautical miles northeast of the central basin of the Challenger Deep at 12 degrees 57 minutes north latitude and 143 degrees 37 minutes east longitude. AUV Urashima dives #90-94 reach a maximum depth of 3500 meters and include a Reson SEABAT7125 AUV multi-beam echo sounder for depth surveying and multiple probes for detecting and mapping trace elements ejected into the water from hot water. successfully surveyed all three sites using water testing equipment from Vents, white smokers, hotspots. Ms. Kyoko Okino of the University of Tokyo's Ocean Research Institute served as the chief scientist on this cruise. Cruise's second goal was to deploy a new "10K free-fall camera system" called Ashura to sample sediments and biologics on the bottom of the Challenger Deep. The principal investigator of the Challenger Deep was Taishi Tsubouchi of the Japan Agency for Marine-Earth Science and Technology. Lander Ashura descended twice. The first, on July 6, 2009, Ashura touched down at 11°22.3130'N, 142°25.9412'E, 10,867 meters (35,653 feet). The second descent (July 10, 2009) was to 11°22.1136'N, 142°25.8547'E, to an elevation of 10,897 meters (35,751 feet). Weighing 270 kg, the Ashura was equipped with multiple baited traps, an HTDV video camera, and equipment to retrieve sediment, water, and biological samples (mainly bait amphipods, bacteria and fungi from sediment and water samples). was equipped.

On October 7, 2010, further sonar mapping of the Challenger Deep region was performed by the US Coastal Ocean Mapping Center/Joint Hydrographic Center (CCOM/JHC) aboard the 4.762-ton Sumner. The results were reported at the American Geophysical Union Fall Annual Meeting in December 2011. The CCOM/JHC team used a Kongsberg Maritime EM 122 multibeam echo sounding system combined with a positioning device capable of measuring latitude and longitude with an accuracy of up to 50 cm (20 inches) from thousands of individual soundings around the deepest depths. I tentatively determined that the Challenger was lurking. The maximum depth of the Deep is 10,994 m (36,070 ft) at 11.326344 N 142.187248 E / 11.326344. 142.187248, the estimated vertical uncertainty is ±40 m (131 ft) with a confidence level of 2 standard deviations (that is, ≈ 95.4%). A secondary depth of 10,951 m (35,928 ft) depth was located approximately 23.75 nautical miles (44.0 km) east, at 11.369639°N 142.588582°E / 11.369639°E. 142.588582 in the eastern basin of Challenger Deep.

JAMSTEC returned Yokosuka to Challenger Deep on November 21-28, 2010 on the YK10-16 cruise. The principal investigator of this joint Japanese-Denmark expedition was Hiroshi Kitasato of the JAMSTEC Biogeoscience Institute. The title of the cruise is 'Biogeoscience of the Challenger Deep: Relationships between Relict Organisms and Biogeochemical Cycles'. The Japanese team deployed five 11,000-meter camera systems (3–6,000 meters, two in the central basin of the Challenger Deep) with 15 sediment cores, video recordings, and 140 predatory amphipods. A similar specimen was collected. The Danish Ultra Deep Lander system was used by Ronnie Grude and others on four casts, two into the central basin of Challenger Deep and two to 6,000 meters, about 34 nautical miles west of the central basin. The deepest recorded depth was November 28, 2010 – Cameracast CS5 – 11°21.9810'N 142°25.8680'E} with a corrected depth of 10,889.6 meters (35,727 feet) (central basin).

JAMSTEC Cruises YK13-09 and YK13-12 Yokosuka invited Senior Research Scientist Hidetaka Nomaki to travel to New Zealand waters (YK13-09) and the return cruise was identified as YK13-12. The project name was QUELLE2013. The cruise was titled 'Field Experimental and Sampling Studies to Understand Deep Sea Biodiversity and Biogeochemical Cycles'. They spent a day at Challenger Deep on their return trip to obtain the DNA/RNA of a large amphipod (Hirondelea gigas) that lives in Challenger Deep. Hideki Kobayashi (Biogeos, Japan Agency for Marine-Earth Science and Technology) and team tested 11 baited traps (3 bald, 5 covered with insulation, 3 after 9 hours) on November 23, 2013. A benthic lander with self-sealing) was deployed in the central basin of Challenger Deep at 11:00. 21.9082′N 142°25.7606′E, 10,896 meters (35,748 feet) deep. After staying on the seafloor for 8 hours and 46 minutes, about 90 Hirondelea giga were recovered.

From January 11 to 17, 2014, JAMSTEC re-deployed Kairei to the Challenger Deep under the direction of Senior Researcher Takuro Fura. The cruise identifier was KR14-01 and the title was "Mariana Trench, Challenger Deep Trench Biosphere Expedition". The expedition collected samples at six stations across the central basin, but only twice with the lander "11-K Camera System" for sediment cores and water samples, and at the deepest "Station C", i.e. 11N latitude. It was deployed at 22.19429'N, 142°25.7574N. Longitude east, elevation 10,903 meters (35,771 feet). Other stations were surveyed on both the northern back-arc and the southern Pacific plate using the 'multi-core' lander. A crawler-driven ROV ABIMSO with a 11,000-meter capability will be deployed approximately 20 nautical miles due north of the Central Basin to identify potential hydrothermal activity, particularly on the northern slopes of the Challenger Deep, as the findings suggest. Sent to 7,646 meters (ABISMO dive #21). From the 2008 Kailey Cruise KR08-05. AMISMO's dives #20 and #22 were approximately 15 nautical miles north of the deepest waters of the Central Basin to an altitude of 7,900 meters. Under the guidance of Laura Calgati of the Polytechnic University of Marche (UNIVPM), Italy, Italian researchers were investigating the dynamics of virus-prokaryote interactions in the Mariana Trench.

From December 16-19, 2014, the Schmidt Oceanographic Institute's 2,024-tonne research vessel Falcor, under the leadership of Douglas Bartlett, Principal Scientist at the Scripps Institute of Oceanography, conducted four different untethered instruments in Challenger Deep. , and made a total of 7 discharges. Her four landers were deployed to the Central Basin on 16 December. Lander ARI reaches 11°21.5809'N 142°27.2969'E for water chemistry. Both Deep Sound probes recorded sounds suspended at a depth of 9,000 meters (29,528 feet) until Deep Sound 3 imploded at a depth of 8,620 meters (28,281 feet) (approximately 2,200 meters (7,218 feet)). bottom. Above the bottom) Latitude 11°21.99'N, Longitude 142°27.2484'E. Deep Sound 2 recorded the implosion of Deep Sound 3 and provided a unique record of an implosion within a depression in Challenger Deep. In addition to the loss of Deep Sound 3 to implosion, lander ARI did not respond to instructions to drop its weight and was never recovered. On December 16th or 17th, Leggo was returned to the central basin as amphipod food. On the 17th, RV Falco moved 17 nautical miles east to the East Basin, where she again deployed both Leggo (baited and fully loaded with cameras) and Deep Sound 2. Deep Sound 2 was programmed to descend to an altitude of 9,000 meters (29,528 meters). ft), the sound in the trench remains at that depth during recording. On December 19, Lego landed at 11°22.11216'N, 142°35.250996'E, at an uncorrected depth of 11,168 meters (36,640 feet), according to pressure sensor readings. This measurement was corrected to a depth of 10,929 meters (35,856 feet). Lego returned with good photos of amphipods feeding on the lander's mackerel, as well as amphipod samples. Faulkner departed Challenger Deep on 19 December, en route from the Mariana Trench Marine National Monument to the Sirena Deep. RV Falkor is equipped with Kongsberg EM302 and EM710 multi-beam echo sounders for bathymetric surveying and Oceaneering C-Nav 3050 global navigation capable of calculating geodetic position with horizontal accuracy of better than 5 cm (2.0 in) and 15 cm (5.9 in) It was equipped with both satellite system receivers. )Vertical direction.

From July 10 to 13, 2015, the Guam-based 1,930-ton U.S. Coast Guard Cutter Sequoia (WLB 215) was transported by National Oceanic and Atmospheric Administration Pacific Marine Environmental Laboratory (PMEL) Principal Investigator Robert P. Ziak. We accepted a team of researchers led by Mr. The University of Washington and Oregon State University are collaborating to deploy PMEL's "full-depth mooring," a 45-meter long moored deep-sea hydrophone and pressure sensor array in the western basin of Challenger Deep. A 6-hour descent into the West Basin anchored the array at a depth of 10,854.7 ± 8.9 m (35,613 ± 29 ft), 11°20.127'N, 142°12.0233'E, approximately 1 km NE of Sumner's deepest depth. . After 16 weeks, the moored array was recovered on November 2-4, 2015. "Observed sound sources included seismic signals (T-phase), whisker and odontocet calls, ship propeller sounds, air guns, active sonar, and categorical passages," Typhoon 4. The scientific team described the results as "the first multi-day broadband recording of environmental sounds at Challenger Deep, and the fifth direct depth measurement."

3,536-ton research vessel Xiangyang Hong09 deployed on the second leg of the 37th China Cruise Dayang (DY37II) sponsored by the Qingdao National Deep Sea Center and the Institute of Deep Sea Science and Technology, Chinese Academy of Sciences (Sanya, Hainan), 2016 From June 4th to July 12th, to the Challenger Deep Western Basin area (11°22'N, 142°25'E). As the mothership of China's manned deep submersible, Jiaolong, the expedition will conduct exploration of the Challenger Deep to investigate the geological, biological and chemical features of the Hadar Zone. The dive area for this leg was on the south slope of Challenger Deep in water depths of approximately 6,300 to 8,300 meters (20,669 to 27,231 feet). The submarine completed nine piloted dives to depths of 5,500 to 6,700 meters (18,045 to 21,982 feet) in the northern back arc and southern area (Pacific Plate) of Challenger Deep. During the voyage, Jiaolong regularly deployed hermetic samplers to collect water near the seafloor. In a test of navigation proficiency, Jiaolong used the Ultra Short Baseline (USBL) positioning system at depths of over 6,600 meters (21,654 feet) to retrieve sampling bottles.

From June 22nd to August 12th, 2016 (Cruise 2016S1 and 2016S2), the Chinese Academy of Sciences 6,250-ton diving support vessel "Tanchao-1" (meaning: explore) sailed from its home port of Sanya to Challenger Deep. set out on its maiden voyage. Hainan Island. On July 12, 2016, ROV Haidu 1 dived to a depth of 10,767 meters (35,325 feet) in the Challenger Deep region. They also dropped a free-fall lander, a 9,000-meter (29,528-foot) rated free-fall seafloor seismic instrument (deployed to 7,731-meter (25,364-foot)), obtained sediment core samples, and ranged from We collected over 2,000 biological samples from depths of 5,000 to 10,000 meters (16,404 to 32,808 feet). Tansuo 01 operated along the line of longitude 142°30'00", about 30 nautical miles east of the previous DY37II cruise survey (see Xiangyang Hong 09 above).

In November 2016, sonar mapping of the Challenger Deep region was performed by the Royal Dutch Institute of Oceanography (NIOZ)/GEOMAR Helmholtz Center for Marine Research Kiel aboard the 8,554-ton deep sea research vessel Sonne. Results were reported in 2017. Using a Kongsberg Maritime EM 122 multi-beam echo sounding system combined with a positioning device capable of determining latitude and longitude, the team determined the maximum depth of Challenger Deep to be 10,925 meters (35,843 feet) at 11 degrees 19.945 meters. Latitude 142° 12.123' E (11.332417° N 142.20205° E / 11.332417; 142.20205), estimated vertical uncertainty is ±12 m (39 ft) at one standard deviation (approximately 68.3%) confidence level. A sonar survey analysis yielded a grid resolution of 100 by 100 meters (328 feet by 328 feet) at bottom depth, so small depressions in the seabed below that size would be difficult to detect with a 0.5 by 1 degree sonar. . Emissions at sea level. Each 0.5 degree beamwidth sonar ping expands to cover a circular area approximately 96 meters (315 feet) in diameter at a depth of 11,000 meters (36,089 feet). The horizontal position of grid points has an uncertainty of ±50 to 100 m (164 to 328 ft) depending on the direction along or across the railroad tracks. This depth (59 m (194 ft)) and position (approximately 410 m (1,345 ft) to the NE) measurements differ significantly from the deepest point measured by Gardner et al. (2014) Research. The depth discrepancies observed in the 2010 sonar mapping and Gardner et al.'s 2014 study are related to the application of different sound speed profiles, which are essential for accurate depth determination. Sonne used the CTD cast used to calibrate and optimize the sound velocity profile approximately 1.6 km west of the deepest exploration depth to near the bottom of the Challenger Deep. Similarly, the effects of using different projections, datums, and ellipsoids during data acquisition can lead to position discrepancies between surveys.

In December 2016, CAS's 3,300-tonne research vessel Shiyan 3 deployed 33 broadband seismometers in both the northwest backarc and southeast of the Challenger Deep near the South Pacific Plate to a depth of 8,137 meters (26,696 feet). Deployed. This cruise was part of a $12 million China-US cruise. An initiative led by Jiang Lin, co-leader of the Woods Hole Oceanographic Institution. A five-year (2017-2021) effort to image Challenger Deep and its surrounding rock formations in detail.

Zhang Jian, a newly launched 4,800-tonne research vessel (and mother ship of the Rainbow Fish series of deep-sea submersibles), left Shanghai on December 3rd. Their cruise would test three new deep-sea landers, an unmanned search submersible, and a new Rainbowfish 11,000-meter manned deep submersible that can dive to 10,000 meters. From 25 to 27 December, three deep-sea landing gear descended into the trench. The first Rainbow Fish Lander took pictures, the second a sediment sample, and the third a biological sample. All three landers reached altitudes of over 10,000 meters, and the third device brought back 103 amphipods. Cui Weicheng, director of the Hudar Life Science Research Center at Shanghai Ocean University, led a team of scientists to conduct research in the Challenger Deep of the Mariana Trench. The vessel is part of China's National Oceanographic Research Fleet, but is owned by a Shanghai-based marine technology company.

From January 20 to February 5, 2017, the CAS Deep Sea Science and Technology Laboratory operated Tan Suo 1 with baited traps to capture fish and other macrobiology near Challenger Deep and Sirena Deep. Sponsored the return to Challenger Deep (Cruise TS03). On January 29, they recovered photographs and samples of a new species of snail, newly designated Pseudoliparis swirei, from the 7,581-meter (24,872-foot) northern slopes of Challenger Deep. They also installed four more CTD casts in the central and eastern basins of the Challenger Deep as part of the World Ocean Circulation Experiment (WOCE).

From January 20 to February 5, 2017, Tokyo University of Marine Science and Technology will operate the research vessel Shinyo Maru equipped with baited traps to capture fish and other macrobiology near the Challenger and Sirena trenches at Marianas. sent to the trench. On January 29, they recovered photographs and samples of the new snail species from the 7,581-meter (24,872-foot) northern slopes of Challenger Deep. This snail was newly designated as Pseudoliparis swirei.

In March 2017, water samples were collected from layer 11 of the Mariana Trench at Challenger Deep. Seawater samples were collected from 4 to 4,000 m depth by Niskin bottles mounted on a Seabird SBE25 CTD. Meanwhile, water samples from 6,050 m to 8,320 m depth were collected by an in-house designed, acoustically controlled, full-ocean depth water sampler. In this study, scientists studied pico- and nanoplankton RNA from the surface to the hadal zone.

JAMSTEC deployed Kairei to Challenger Deep in May 2017, under the leadership of Chief Scientist Takashi Murashima, to test the new full-sea depth ROV UROV11K (underwater ROV 11,000 meters capable) as a cruising KR 17-08C. I took a purpose. The title of the cruise is "Sea Test of Full Depth ROV UROV11K System in Mariana Trench". The UROV11K was equipped with a new 4K high-definition video camera system and new sensors for monitoring hydrogen sulfide, methane, oxygen and hydrogen content in water. Unfortunately, when the UROV11K ascended from an altitude of 10,899 meters (35,758 feet) on May 14, 2017 (East Basin, near 11°22.30'N, 142°35.8°E), the ROV's buoyancy was 5,320 degrees deep. It failed at 17,454 feet and attempts to retrieve the ROV were unsuccessful. The descent and drift speeds are unknown, but the ROV landed east of the deepest waters of the East Basin, as revealed by maneuvers on May 14. Murashima then guided the Kairei to a location about 35 nautical miles east of the eastern basin of Challenger Deep to test the new Compact Hadal Lander and to test and photograph Sony's 4K camera. Three descents from 7,498 meters to 8,178 meters. Fish and other macrobiological logic.

During its maiden voyage, the 2,150-ton catamaran scientific research vessel Shenguo (also known as Shengguo, Shengang, or Shenguo) left Shanghai on November 25, 2018 and returned to port on January 8, 2019. bottom. These vessels operated in the Mariana Trench and, on December 13, tested an underwater navigation system in over 10,000 meters of water during a field test of the Tsaihungyuy (ultra-short baseline) system. Project leader Tsui Beichen said that in the deep sea, Caihunyui's equipment can be used to acquire signals and determine precise geolocation. The research team from Shanghai Ocean University and West Lake University was led by Weicheng Cui, director of the Hudar Science and Technology Research Center (HSRC) at Shanghai Ocean University. Equipment under test included a maneuverable submarine (achieved depths are not available as they are not full depths) and two deep-sea landers, both submersible to depths of 10,000 meters. and includes an ROV that can reach up to 4,500 meters. They took photographs and collected samples of water, sediment, macrobiology and microbes from the trenches. Choi said, "If we can photograph fish at depths of 8,145 meters or more... we will break the current world record. We will be testing new equipment, including landing gear. Those are the second generation. The first generation." I just couldn't do this," he said. “Usually we sample at one location per dive, but this new second generation allows us to sample at different depths in a single dive. We also tested an ultra-short baseline acoustic positioning system on a boat.”

In November 2019, as the SR1916 cruise, the NIOZ team led by Chief Scientist Hans van Haren and Scripps engineers deployed to the Challenger Deep aboard the 2,641-ton research vessel Sally Ride and moored from the Challenger West Basin. The cord was recovered. deep. The 7 km (4.3 mi) long mooring line at Challenger Deep consists of two sections of top flotation, Dyneema neutral buoyancy 6 mm (0.2 in) line, located at a depth of approximately 4 km (2.5 mi). It consisted of two benthos acoustic releases and two sections. Built-in instruments that measure and store current, salinity and temperature. Two ammeters were mounted below a 200 m (656 ft) long array of 100 high-resolution temperature sensors at a depth of approximately 6 km (3.7 miles). Starting at a height of 600 m (1,969 ft) above the seafloor, 295 specially designed high-resolution temperature sensors were mounted at low positions, the lowest of which was 8 m (26 ft) above the trench floor. The mooring lines were deployed by the NIOZ team during the RV Sonne expedition in November 2016 and left to be retrieved by Sonne in late 2018. An acoustic command release mechanism near the bottom of Challenger Deep failed in a 2018 attempt. The RV Sally Ride was only available for one last attempt to retrieve the mooring line before the battery in the release mechanism ran out. Sally Ride arrived at Challenger Deep on 2 November. This time a "deep release unit" lowered to a depth of about 1,000 meters by one of Sally Ride's winch cables sounded a release command and managed to make contact with the release near the bottom. After nearly three years of submersion, 15 of the 395 temperature sensors developed mechanical problems. The first results indicate that internal waves are occurring at Challenger Deep.

The maximum sonar mapping depth in 2010 reported by Gardner et.al., 2014 and Greenaway et al. The 2021 study has not been confirmed by direct drop (manometer/manometer) measurements at full sea depth. The expedition reports a direct measured maximum depth in a narrow range. The maximum depth of the Western Basin was reported by Trieste in 1960 as 10,913 m (35,804 ft), and by the June 2020 DSV limit factor as 10,923 m (35,837 ft) ±4 m (13 ft). The maximum reported depth for the central basin is 10,915 m (35,810 ft) ±4 m (13 ft) per DSV limit factor for June 2020. In the eastern basin, the deepest depths were 10,911 m (35,797 ft) by Rov Kaikou in 1995, 10,902 m (35,768 ft) by Rov Nereus in 2009, and 10,908 M (35,787 ft) by Deepsea Challenger in 2012, 10,929 M (reported by 35,856 FT.) 10,925 m (35,843 ft) ± 4 m (13 ft) in May 2019 by benthic lander "Leggo" and by DSV limit factor in May 2019.

On January 23, 1960, the Swiss-designed Trieste, originally built in Italy and purchased by the US Navy, descended to the bottom of the trench, assisted by USS Wandunk (ATF 204) and escorted by USS Lewis (DE 535). bottom. It was piloted by Jacques Piccard (who co-designed the submarine with his father Auguste Piccard) and U.S. Navy Lieutenant Don Walsh. Their crew compartment was in a spherical pressure vessel 2.16 meters in diameter suspended below an 18.4 meters long buoyancy tank. It was a heavy-duty alternative (to the Italian original) manufactured by Krupp Steelworks in Essen, Germany. The steel walls were 12.7 cm thick and were designed to withstand pressures of up to 1250 kilograms per square centimeter (1210 atmospheres, 123 MPa). The descent took nearly five hours, with the pair spending just 20 minutes on the seafloor before ascending in 3 hours and 15 minutes. The early departure from the seafloor was due to concerns over cracks in the outer windows caused by temperature differences during descent. Trieste dived at or near 11°18.5'N, 142°15.5'E and had a bottom point of 10,911 meters (35,797 meters). ft) ±7 m (23 ft) to the western basin of Challenger Deep (as measured by onboard pressure gauges). Another source states that the bottom depth reading was taken using a pressure gauge at 10,913 m (35,804 ft) ±5 m (16 ft). Support vessel navigation was by Celestial and LORAN-C with an accuracy of 460 meters (1,510 feet) or better. Fischer noted that Trieste's reported depth "matches well with the resonance of the sound."

On March 26, 2012 (local time), Canadian filmmaker James Cameron made a solo descent to the bottom of the Challenger Deep on the DSV Deepsea Challenger. On 26th March he began his descent at around 05:15 ChST (19:15 UTC on 25th March). At 07:52 ChST (21:52 UTC), the Deepsea Challenger reached the seafloor. The descent lasted 2 hours and 36 minutes, with a recorded depth of 10,908 meters (35,787 feet) when the Deepsea Challenger landed. Prime Minister Cameron had planned to spend about six hours exploring near the seafloor, but decided to begin the ascent to the surface after just two hours and 34 minutes. A hydraulic leak in the line controlling the manipulator arm blocked the view from the only observation port, thus shortening the bottom time. It also caused the loss of the submarine's starboard thrusters. According to the Deepsea Challenger website, around 12:00 CST (2:00 UTC March 26), the submarine resurfaced after a 90-minute ascent, while Paul Allen tweeted: It took about 67 minutes to ascend. "I landed on a very soft, almost gelatinous flat surface," Cameron said at a post-dive press conference. ' said. Cameron said he had not seen any fish or creature larger than an inch (2.54 cm) in length during that time. "All I saw were free-swimming small amphipods," bottom eaters like shrimp.

The objective of the Five Deeps expedition was to thoroughly map and visit the deepest points in all five oceans of the world by the end of September 2019. On April 28, 2019, explorer Victor Vescovo landed at the "East Pool" of Challenger Deep in the Deep. - Submerged Vehicle Limit Factor (Triton 36000/2 model underwater vehicles). Between 28 April and 4 May 2019, Limiting Factor completed four dives to the bottom of Challenger Deep. The fourth dive descended into the somewhat shallower 'central pool' of Challenger Deep (crew: Patrick Leahay, pilot, John Ramsay, sub-designer). The Five Deeps Expedition estimated maximum depths of 10,927 meters (35,850 feet) ± 8 meters (26 feet) and 10,928 meters (35,853 feet) ± 10.5 meters (34 feet) at 11.3693°N 142.5889°E / 11.3693;142.5889; Did. Investigation of the operating area by direct CTD pressure measurements and the pressure drop of the Deepwater Support Vessel DSSV, a support vessel equipped with a Kongsberg SIMRAD EM124 multibeam echo sounder system. The CTD measured pressure at seawater depth of 10,928 m (35,853 ft) was 1,126.79 bar (112.679 MPa; 16,342.7 psi). Due to technical problems, the (unmanned) ultra-deepwater lander Scaff used by the Five Deeps expedition was limited by the limiting factor (crew: Patrick Rayhey, pilot, Jonathan Struwe, DNV GL specialist) to an estimated Taken from a depth of 10,927 m (35,850 ft). The data collected was made public with the caveat that it is subject to further analysis and may be corrected in the future. Data will be donated to the GEBCO Seabed 2030 initiative. In late 2019, after reviewing depth data and multiple sensor recordings acquired by the DSV Limiting Factor and the ultra-deep water landers Crossp, Flare and Scuff, the Five Deeps expedition reached a maximum depth of 10,925 m (35,843 ft). Fixed. ±4 m (13 ft).

Karadan Oceanic's "Ring of Fire" expedition in the Pacific included six crew drops into all three basins of Challenger Deep and the deployment of 25 landers, all of Victor Piloted by Vescovo, it also surveyed the terrain and marine life throughout Challenger Deep. The expedition vessels used were the deepwater support vessel DSSV Pressure Drop, the deepwater diving vehicle DSV Limiting Factor, and the ultra-deepwater lander Crosp, Flail and Scuff. During its first manned dive on June 7, 2020, Victor Vescovo and former US Astronaut (former NOAA Director) Kathryn D. Descended into the East Pool. On June 12, 2020, Victor Vescovo and mountaineer and explorer Vanessa O'Brien descended into the "East Pool" of Challenger Deep and spent three hours mapping the floor. O'Brien said her dive scanned about a mile of inhospitable seafloor and found that the surface wasn't as flat as once thought, but sloped about 18 feet (5.5 meters). is, of course, subject to verification. On June 14, 2020, Victor Vescovo and John Lost descended into the "East Pool" of Challenger Deep, a deep dive vehicle limiting factor, spending four hours at depth and passing approximately two miles through the seafloor. On June 20, 2020, Victor Vescovo and Kelly Walsh landed in Challenger Deep's "Western Pool", a deep-submerged vehicle restriction factor, and spent four hours at the bottom. The maximum depth reached 10,923 m (35,837 ft). Kelly Walsh is the son of Don Walsh, captain of Trieste with Jacques Piccard in 1960. On June 21, 2020, Victor Vescovo and Woods Hole Oceanographic Institution researcher Ying Zhong Lin landed in the "central pool" at Challenger depth, a deep-submersion vehicle limiting factor. Maximum depth reached 10,915 m (35,810 ft) ±4 m (13 ft). On June 26, 2020, Victor Vescovo and Jim Wigginton landed in the 'East Pool' of Challenger Deep, a deep submerged vehicle limiting factor.

The Fendouzhe (奋斗者, Striver) is a Chinese manned deep-sea submersible developed by the China Ship Science and Research Center (CSSRC). Between October 10 and November 28, 2020, 13 dives were performed in the Mariana Trench as part of the test program. Eight of them reached depths greater than 10,000 m (32,808 ft). On November 10, 2020, Fenduse reportedly reached the bottom of the Challenger Deep with three Chinese scientists (pilots, Zhang Weizhang, Zhaoyang Zhaoyang and Wang Zhiqiang) on ​​board. Live streamed the descent to depth. 10,909 meters (35,791 feet). This makes the Fenduse the fourth manned submersible to land successfully. The Fenduse's pressure-resistant hull is made from a newly developed titanium alloy and features space for three people in addition to technical equipment. Fendouzhe is equipped with a camera from Norwegian manufacturer Imenco. According to the submarine's chief designer, Ye Kong Yeo, China's goal in this dive is not only scientific research, but also the future exploitation of deep-sea resources.

On February 28, 2021, Karadan Oceanic's "Ring of Fire 2" expedition arrived over Challenger Deep and conducted a manned descent and lander deployment onto Challenger Deep. Initially, the (unmanned) ultra-deepwater lander Scaff was deployed to collect water column data by CTD for the expedition. The impact of the Pacific subducting plate colliding with the Philippine plate was also included among those investigated in the field. On 1 March 2021, the first manned descent into the East Pool was made by Victor Vescovo and Richard Garriott. Garriott became the 17th person to drop to the bottom. On March 2, 2021, the descent to the eastern pool was carried out by Victor Vescovo and Michael Dubno. The descent into the eastern pool was carried out on 5 March by Victor Vescovo and Hamish Harding. They crossed the bottom of Challenger Deep. On March 11, 2021, the descent into the western pool was carried out by Victor Vescovo and marine botanist Nicole Yamase. On April 13, 2021, deep sea submarine pilots Rob McCallum and Tim McDonald piloted the dive and made the descent. A Japanese descent is scheduled for 2021. All manned descents were conducted within the DSV limit factors for deep submerged vehicles.

In July 2022, for the fourth year in a row, Karadan Oceanic's deepwater diving system, consisting of a deepwater DSV limiting factor supported by a mothership DSSV pressure drop, returned to Challenger Deep for a dive to Challenger Deep. In early July 2022, Victor Vescovo joined Aaron Newman as a mission specialist for a dive into the Central Pool. On July 5, 2022, Tim McDonald flew into the eastern pool as pilot and Jim Kitchen as mission specialist. On July 8, 2022, Victor Vescovo joined Dylan Taylor as a mission specialist for a dive to the Eastern Pool. Victor Vescovo (15th dive to Challenger Deep) with geographer and oceanographer Dawn Wright as Mission Specialist for the July 12, 2022 dive to 10,919 meters (35,823 feet) in the Western Pool accompanied. Wright operated the world's first sidescan sonar operating at full sea depth to capture detailed images along a short cross-section of the western pool's south wall.

The Remotely Operated Vehicle (ROV) Kaiko made multiple unmanned descents into the Mariana Trench from the support vessel RV Yokosuka during two expeditions in 1996 and 1998. From February 29th to March 4th, the ROV "Kaikou" dived into the central basin three times, "Kaikou 21" and "Kaikou 23". Depths ranged from 11°22.536'N 142°26.418'E 10,898 meters (35,755 ft) to 11°22.59'N 142°25.848'E 10,896 meters (35,748 ft). #22 and #23 dive north while #21 dives northeast of the deepest waters of the Central Basin. During the 1996 measurements, sampling station temperature (water temperature rises at depth due to adiabatic compression), salinity, and water pressure were 2.6 °C (36.7 °F), 34.7 percent, 1,113 bar (111.3 MPa; 16,140 psi). was. Each is 10,897 m (35,751 ft) deep. Japan's robotic deep-sea probe Kaiko reached near the bottom of the Challenger Deep, breaking the depth record for an unmanned probe. Developed by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), it was one of the few operating unmanned deep-sea probes capable of diving deeper than 6,000 meters (20,000 feet). At 11°22.39'N, 142°35.54'E, the pressure gauge measured depth of Challenger Deep was 10,911.4 m (35,799 ft) ±3 m (10 ft), the most accurate depth ever measured. considered to be a measurement. According to another source, the maximum depth measured by KAIKO in 1996 was 10,898 meters (35,755 feet) at 11°22.10'N 142°25.85'E, and 10,907 at 11°22.95'N 142°12.42'E in 1998. meters (35,784 feet). The ROV KAIKO was the first vehicle to visit the bottom of the Challenger Deep since the 1960 Bathyscaphe Trieste dive, and was the first to successfully sample sediment and mud from the bottom of the trench. A sample was taken. About 3,000 microorganisms were identified from the samples. Kaikou was wrecked off the coast of Shikoku by Typhoon Changhong on May 29, 2003.

From May 2 to June 5, 2009, RV Kilo Moana hosted the Woods Hole Oceanographic Institution's (WHOI) Hybrid Remotely Operated Vessel (HROV) Nereus Team, the first Nereus in 3-ton combined ROV mode. was tested in operation. The Nereus team was led by WHOI expedition leader Andy Bowen, Johns Hopkins University's Louis Whitcomb, and WHOI's Dana Jorger. The expedition has co-chief scientists, WHOI biologist Tim Shank and University of Hawaii geologist Patricia Fryer, who will take advantage of the ship's bathymetric terrain and create a scientific team to organize the scientific experiments deployed by Nereus. was leading. Tests gradually increased in depth and complexity of seafloor activity until Nereus #007ROV dived to 880 m (2,887 ft) just south of Guam and #010ROV dived to Nero depths at 9,050 m (29,692 ft). has increased. On dive #011ROV on May 31, 2009, Nereus was piloted on a 27.8 hour underwater mission, traversing the eastern basin of Challenger Deep for approximately 10 hours from the south face to the northwest to the north face, streaming live video and data. Did. Return to mothership. The maximum depth of 10,902 m (35,768 ft) was recorded at 11°22.10'N, 142°35.48'E. The RV Kilo Moana then moved to the West Basin, where a 19.3 hour underwater dive reached a maximum depth of 10,176 m (33,386 ft) in the same area (11°19.59°N, 142°E 12.99°E). Nereus successfully used its manipulator arm to retrieve both sediment and rock samples from the eastern and western basins for further scientific analysis. HROV's final dive was 2,963 meters (9,721 feet) in the TOTO caldera (12°42.00°N, 143°31.5°E) within a backarc approximately 80 nautical miles (148.2 km) north of Challenger Deep. Nereus thus became the first probe to reach the Mariana Trench since 1998 and the deepest dive probe in service at the time. Project manager and developer Andy Bowen hailed the achievement as "the beginning of a new era in ocean exploration." Unlike Kaikou, Nereus did not need to be powered or controlled by cables connected to ships on the surface. HROV Nereus went missing on 10 May 2014 while diving at a depth of 9,900 meters (32,500 feet) in the Kermadec Trench.

In June 2008, the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) dispatched the research vessel Kairei to the Guam area for Cruise KR08-05 Legs 1 and 2. On June 1-3, 2008, during leg 1, the Japanese robotic deep-sea probe ABISMO (Automated Seabed Inspection and Sampling Mobile) dives 11-13, immersed in the seafloor approximately 150 km (93 miles) east of Challenger Deep. has almost reached Unfortunately, the primary cable of the KAIKO system was a little short, so it was not possible to dive to the seafloor. Twelve water samples were also taken at various depths..." ABISMO's dive #14 was the TOTO caldera (12°42.7777N, 143°32.4055E), about 60° northeast of the deepest part of the Central Basin. It was nautical. We got a video of the hydrothermal plume at the Challenger Deep. JAMSTEC's ROV ABISMO was successfully tested to 10,000 m (32,808 ft), making it the only fully depth-rated ROV in existence. On May 31, 2009, ABISMO was joined by Woods Hole Oceanographic Institution's HROV Nereus, making it the only surviving remotely operated rover capable of operating at all ocean depths. During ROV ABISMO's deepest seaway dive, the pressure gauge measures 10,257 m (33,652 ft) ±3 m (10 ft) at "Area 1" (near 12°43'N, 143°33'E) Did. Leg 2, under Chief Scientist Takashi Murashima, operated June 8-9, 2008 at Challenger Deep, testing JAMSTEC's new full-depth "free-fall mooring system," or lander. The lander took video images and sediment samples at 11°22.14'N, 142°25.76'E in the central basin of the Challenger Deep and conducted two tests to a depth of 10,895 meters (35,745 feet). Successful.

On May 23, 2016, the Chinese submarine Haidu-1 dived to a depth of 10,767 meters (35,325 ft) at an undisclosed location in the Mariana Trench, with China serving Japan (ROV Kaikou) and the United States (HROV Nereus). became the third country after , to deploy full-depth marine ROVs. The design depth of this autonomous remotely operated vehicle is 11,000 m (36,089 ft).

On May 8, 2020, the Russian submarine Vityaz-D dived to a depth of 10,028 meters (32,900 feet) at an undisclosed location in the Mariana Trench.

The summary report of the HMS Challenger Expedition lists radiolaria from two dredged samples taken when Challenger Deep was first discovered. These (Nassararia and Spumeraria) were reported in a report on radiolarians (1887) written by Ernst Haeckel. During the 1960 descent, the Trieste crew noticed that the floor was made of diatomaceous earth and reported observing "some sort of flounder" lying on the seafloor. And when I was unraveling this last truth, I saw something wonderful. On the bottom just below us lay a kind of flounder like flounder about 30cm long and about 15cm wide. Even when I saw him, the two round eyes above his head were watching us, the steel monsters, invading his realm of silence. eye? why does he have eyes? Is it just to see the phosphorescence? The floodlight that illuminated him was the first real light that entered this underworld. The answer biologists have been looking for for decades is here, in an instant. Is it possible that there is life in the deepest part of the ocean? And not only that, but apparently there were real bony fishes here, not primitive rays or elasmobranchs. Yes, highly evolved vertebrates, the arrow of time is very close to humanity itself. Slowly, very slowly, this flounder swam away. Traveling along the seabed, partly in mud and partly in water, he disappeared into the night. Slowly, perhaps everything is slow at the bottom of the ocean, Walsh and I shook hands. Many marine biologists are now skeptical of the sighting, suggesting it might be a sea cucumber. A video camera mounted on the Kaiko spacecraft captured sea cucumbers, scale insects, and shrimp on the seafloor. At the bottom of Challenger Deep, the Nereus spacecraft discovered a single polychaete (multi-legged predator) about an inch long. Analysis of sediment samples collected by Kaiko found numerous simple organisms at 10,900 m (35,800 ft). Although similar organisms are known to exist in shallower trenches (>7,000 m) and deep-sea plains, the organisms found at Challenger Deep represent a distinct taxon from shallower ecosystems. there is a possibility. Most of the collected organisms are simple soft-shelled foraminifera (432 species according to National Geographic), while the remaining four correspond to the complex multilocular Leptothallis and Leophax species. Eighty-five percent of the specimens were organic soft-shelled conspecifics, which is unusual when compared to samples of other sediment-dwelling organisms in deep-sea environments, where percentages of organic wall foraminifera range from 5% to 20%. be. Small organisms with hard calcareous shells have difficulty growing at extreme depths due to the high solubility of calcium carbonate in pressurized water, so scientists believe that soft-shelled organisms in Challenger Deep They theorize that the bio-dominance may have been attributed to the typical biosphere that existed at the time. Challenger Deep was shallower than it is today. As the Challenger Deep grew to its present depth over the course of 6 to 9 million years, many of the species present in the sediments either became extinct or became unable to adapt to the increased water pressure and changing environment. On March 17, 2013, researchers reported data suggesting that pressure-loving microbes flourish in Challenger Deep. Other researchers reported a related study that found microbes thriving in rocks up to 579 meters (1,900 feet) below the seafloor, 2,591 meters (8,500 feet) off the coast of the northwestern United States. . According to one of the researchers, "Microbes are everywhere. Microbes are very adaptable to conditions and survive anywhere."

emden deep Horizon Deep List of people who landed on Challenger Deep Deep Litke, the closest point to the center of the Earth Sirena Deep (formerly HMRG Deep)

"Official press release on Operation Challenger Deep". Archived from the original on 2002-04-18. Mariana Trench Mariana Trench: 7 miles deep, the ocean is still a noisy place