View source for Kaikō ROV

{{short description|Japanese remotely operated underwater vehicle for deep sea exploration}}
{|{{Infobox ship begin |display title=''Kaikō'' ROV}}
{{Infobox ship image
|Ship image=JAMSTEC Deep Sea ROV kaikou7000.jpg
|Ship caption=''Kaikō''
}}
{{Infobox ship career
|Hide header=
|Ship country=Japan
|Ship flag=[[File:Flag of Japan.svg|50px]]
|Ship owner=The [[Japan Agency for Marine-Earth Science and Technology]] (JAMSTEC)
|Ship operator=JAMSTEC
|Ship laid down=1991<ref name=Kyo1995/>
|Ship launched=1993<ref name=Kyo1995/>
|Ship completed=1993<ref name=Kyo1995/>
|Ship christened=1993<ref name=Kyo1995/>|Ship maiden voyage=May 1993 to March 1995<ref name=Kyo1995/>
|Ship commissioned=1993<ref name=Kyo1995/>
|Ship recommissioned=
|Ship decommissioned=
|Ship out of service=2003
|Ship renamed=
|Ship reclassified=
|Ship refit=
|Ship struck=2003
|Ship reinstated=
|Ship homeport=[[Yokosuka]], Japan
|Ship identification=
|Ship nickname=
|Ship fate=Lost at sea off [[Shikoku|Shikoku Island]] during [[2003 Pacific typhoon season#Typhoon Chan-hom|Typhoon Chan-Hom]], 29 May 2003<ref name=Ishibashi2008/>
|Ship notes=
|Ship badge=
}}
{{Infobox ship characteristics
|Hide header=
|Header caption=
|Ship type=[[remotely operated underwater vehicle]]
|Ship tonnage=
|Ship displacement=10.6 tons in air<ref name=Kakuchi/>
|Ship length=3.0 meters<ref name=Kakuchi/>
|Ship beam=
|Ship height=
|Ship draft=
|Ship power=electrical ([[Lithium-ion battery|Lithium-ion batteries]])
|Ship propulsion=
|Ship speed=
|Ship range=
|Ship endurance=
|Ship test depth=10911.4 meters
|Ship complement=unmanned
|Ship sensors=[[side-scan sonar]] and search lights
|Ship armor=
|Ship notes=
}}
|}
{{nihongo|'''''Kaikō'''''|かいこう||"Ocean Trench"}}<ref>{{Cite web |title=「かいこう」＜研究船・探査機＜研究船・施設・設備＜JAMSTECについて＜海洋研究開発機構 |url=https://www.jamstec.go.jp/j/about/equipment/ships/kaiko.html |access-date=2022-03-18 |website=www.jamstec.go.jp}}</ref> 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 (including 180 different bacteria), some of which could prove to be useful in medical and industrial applications.<ref name=Kakuchi>{{cite web
 |author=Suvendrini Kakuchi 
 |date=21 July 2003 
 |url=http://www.tierramerica.net/english/2003/0721/iarticulo.shtml 
 |title=The Underwater Wonders Revealed by Kaiko 
 |publisher=Tierramérica: Environment & Development
 |access-date=27 June 2010 
 |url-status=dead 
 |archive-url=https://web.archive.org/web/20110526095906/http://www.tierramerica.net/english/2003/0721/iarticulo.shtml 
 |archive-date=26 May 2011 
}}</ref> On 29 May 2003, ''Kaikō'' was lost at sea off the coast of [[Shikoku|Shikoku Island]] during [[2003 Pacific typhoon season#Typhoon Chan-hom|Typhoon Chan-Hom]], when a secondary cable connecting it to its launcher at the ocean surface broke.<ref name=Ishibashi2008/>

Another ROV, ''Kaikō7000II'', served as the replacement for ''Kaikō'' until 2007. At that time, JAMSTEC researchers began [[sea trial]]s for the permanent replacement ROV, ''[[ABISMO]]'' ('''A'''utomatic '''B'''ottom '''I'''nspection and '''S'''ampling '''Mo'''bile).

==Challenger Deep==
{{Main|Challenger Deep}}
[[File:Marianatrenchmap.png|300px|thumb|left|Location of the [[Challenger Deep]] in the [[Mariana Trench]]]]
[[Bathymetry|Bathymetric]] data obtained during the course of the [[Challenger expedition|expedition]] (December 1872 – May 1876) of the British [[Royal Navy]] survey ship {{HMS|Challenger|1858|6}} enabled scientists to draw maps,<ref>{{cite book
|author1=John Murray |author2=Rev. A.F. Renard |title=Report of the scientific results of the voyage of H.M.S. Challenger during the years 1873 to 1876
|publisher=Her Majesty's Stationery Office
|location=London
|year=1891
|pages=525
|url=http://www.19thcenturyscience.org/HMSC/HMSC-Reports/map-800/b-200.jpg
|access-date=27 June 2010}}</ref> which provided a rough outline of certain major [[List of submarine topographical features|submarine terrain features]], such as the edge of the [[Continental shelf|continental shelves]] and the [[Mid-Atlantic Ridge]]. This discontinuous set of data points was obtained by the simple technique of taking [[Sounding line|soundings]] by lowering long lines from the ship to the [[seabed]].<ref name=Murray1891>{{cite book
 |author1      = John Murray
 |author2      = Rev. A.F. Renard
 |title        = Report on the Deepsea Deposits based on the Specimens Collected during the Voyage of H.M.S. Challenger in the years 1873 to 1876
 |publisher    = Her Majesty's Stationery Office
 |location     = London
 |year         = 1891
 |pages        = 525
 |url          = http://www.19thcenturyscience.org/HMSC/HMSC-Reports/1891-DeepSeaDeposits/htm/doc.html
 |access-date   = 27 June 2010
 |archive-url  = https://web.archive.org/web/20110724205544/http://www.19thcenturyscience.org/HMSC/HMSC-Reports/1891-DeepSeaDeposits/htm/doc.html
 |archive-date = 2011-07-24
 |url-status     = dead
}}</ref>

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 [[surveying|surveyed]] point of the [[World Ocean]]. The ''Challenger'' scientists made the first recordings of its depth on 23 March 1875 at [https://web.archive.org/web/20110310200116/http://www.19thcenturyscience.org/HMSC/HMSC-Reports/1895-Summary/htm/doc878.html station 225]. The reported depth was 4,475 [[fathom]]s (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)|''Trieste'']] [[bathyscaphe]]. Though the initial report claimed the bathyscaphe had attained a depth of 37,800 feet,<ref name=usn1960>{{cite web
 |author=Press Release, Office of Naval Research 
 |date=February 1, 1960 
 |url=http://www.onr.navy.mil/focus/ocean/vessels/submersibles11.htm 
 |title=Research Vessels: Submersibles – ''Trieste'' 
 |publisher=United States Navy 
 |access-date=27 June 2010 
 |url-status=dead 
 |archive-url=https://web.archive.org/web/20020418105908/http://www.onr.navy.mil/focus/ocean/vessels/submersibles11.htm 
 |archive-date=18 April 2002 
}}</ref> the maximum recorded depth was later calculated to be {{convert|10911|m}}. At this depth, the [[water column]] above exerts a [[barometric pressure]] of {{convert|108.6|MPa|psi}}, over one thousand times the [[atmospheric pressure#Standard atmospheric pressure|standard atmospheric pressure]] at sea level. 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.<ref name="James Cameron Now at Ocean's Deepest Point">{{cite web |author=National Geographic |title=James Cameron Now at Ocean's Deepest Point |url=http://news.nationalgeographic.com/news/2012/03/120325-james-cameron-mariana-trench-challenger-deep-deepest-science-sub/ |archive-url=https://web.archive.org/web/20120327053619/http://news.nationalgeographic.com/news/2012/03/120325-james-cameron-mariana-trench-challenger-deep-deepest-science-sub/ |url-status=dead |archive-date=March 27, 2012 |date=25 March 2012 |publisher=National Geographic Society |access-date=25 March 2012 }}</ref>

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.<ref name=Kakuchi/><ref name=BBC/> The maximum depth measured on that dive was 10,911.4 meters,<ref name=Kyo1995>{{cite book
|author1=M. Kyo |author2=E. Hiyazaki |author3=S. Tsukioka |author4=H. Ochi |author5=Y. Amitani |author6=T. Tsuchiya |author7=T. Aoki |author8=S. Takagawa |title=OCEANS '95. MTS/IEEE. Challenges of Our Changing Global Environment (Conference Proceedings)
|chapter=The sea trial of "KAIKO", the full ocean depth research ROV
|volume=3
|location=San Diego, California
|isbn=978-0-933957-14-5
|doi=10.1109/OCEANS.1995.528882
|date=October 1995
|pages=1991–1996
|s2cid=110932870 }}<!--|access-date=27 June 2010--></ref><ref name=BBC>{{cite news
|url=http://news.bbc.co.uk/2/hi/science/nature/8080324.stm
|title=Robot sub reaches deepest ocean
|date=3 June 2009
|publisher=BBC News
|access-date=27 June 2010}}</ref><ref name=JAMSTEC01>{{cite web
|author=JAMSTEC
|year=2007
|url=http://www.jamstec.go.jp/e/about/equipment/ships/kaiko7000.html
|title=Maximum depth reached by ''Kaikō''
|publisher=Japan Agency for Marine-Earth Science and Technology
|location=[[Yokosuka, Kanagawa|Yokosuka]], Japan
|access-date=27 June 2010
|archive-date=15 June 2010
|archive-url=https://web.archive.org/web/20100615055050/http://www.jamstec.go.jp/e/about/equipment/ships/kaiko7000.html
|url-status=dead
}}</ref> 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.<ref name=BBC/><ref name=Moana1>{{cite web
 |author=University of Hawaii Marine Center 
 |date=4 June 2009 
 |url=http://www.soest.hawaii.edu/UMC/Reports/Archives/KMreportAprilMay2009.html 
 |title=Daily Reports for R/V KILO MOANA June & July 2009 
 |publisher=University of Hawaii 
 |location=Honolulu, Hawaii 
 |access-date=27 June 2010 
 |url-status=dead 
 |archive-url=https://web.archive.org/web/20090919155251/http://www.soest.hawaii.edu/UMC/Reports/Archives/KMreportAprilMay2009.html 
 |archive-date=19 September 2009 
}}</ref>

==RV ''Kairei''==
[[File:JAMSTEC Deep Sea Research Ship Kairei.jpg|right|thumb|RV ''Kairei'']]
[[File:JAMSTEC Kairei control room.jpg|thumb|250px|RV Kairei Control Room]]
RV ''Kairei'' ([[:ja:かいれい|かいれい]]) is a deep sea research vessel that served as the support ship for ''Kaikō'', and for its replacement ROV, ''Kaikō7000II''. It now serves as the support ship for ''[[ABISMO]]''. ''Kairei'' uses ''ABISMO'' to conduct surveys and observations of [[oceanic plateau]]s, [[abyssal plain]]s, [[oceanic basin]]s, [[submarine volcano]]es, [[hydrothermal vent]]s, [[oceanic trench]]es and other underwater terrain features to a maximum depth of 11,000 meters. ''Kairei'' also conducts surveys of the structure of deep sub-bottoms with complicated geographical shapes in subduction zones using its on-board multi-channel reflection survey system.<ref name=Kairei>{{cite web
|author=JAMSTEC
|year=2007
|url=http://www.jamstec.go.jp/e/about/equipment/ships/kairei.html
|title=Deep Sea Research Vessel ''KAIREI''
|publisher=Japan Agency for Marine-Earth Science and Technology
|location=[[Yokosuka, Kanagawa|Yokosuka]], Japan
|access-date=27 June 2010}}</ref>

==Timeline and fate of ''Kaikō''==
[[File:JAMSTEC Deep Sea ROV kaikou7000.jpg|thumb|right|300px|The launcher for ''Kaikō'' [[remotely operated underwater vehicle|ROV]].]]
[[File:AMSTEC Deep Sea ROV kaikou7000 Vehicle.jpg|thumb|right|300px|''Kaikō7000II'' 
''Kaikō'' reached a maximum depth of 10,911.4 meters at the Challenger Deep on 24 March 1995, during its initial sea trials.<ref name=Kyo1995/><ref name=BBC/><ref name=JAMSTEC01/> At that time, the craft collected video and photographs of various [[extremophile|barophilic]] [[benthos]], including [[Tube worm (body plan)|tubeworms]] and [[shrimp]].
[[remotely operated underwater vehicle|ROV]] in position under its launcher, aboard the deep sea research ship [[RV Kairei|RV ''Kairei'']].]]
[[File:Hirondellea gigas.jpg|thumb|left|200px|''[[Gammaridea|Hirondellea gigas]]'' specimen at [[Shin-Enoshima Aquarium]], [[Enoshima|Enoshima Island]], [[Fujisawa, Kanagawa]], Japan.]]
In February 1996, ''Kaikō'' returned to Challenger Deep, this time collecting [[sediment]] and [[microorganism]]s from the [[seabed]] at a depth of 10,898 meters. Among the novel organisms identified and collected was ''[[Moritella yayanosii]]''<ref name=Nogi1999>{{cite journal
|author1=Y. Nogi |author2=Chiaki Kato |title=Taxonomic studies of extremely barophilic bacteria isolated from the Mariana Trench and description of Moritella yayanosii sp. nov., a new barophilic bacterial isolate
|journal=Extremophiles
|volume=3
|issue=1
|pages=71–77
|date=January 1999
|pmid=10086847
|doi=10.1007/s007920050101
|s2cid=9565878 }}</ref> and ''[[Shewanella benthica]]''.<ref name=Kato1998>{{cite journal
|author1=Chiaki Kato |author2=Lina Li |author3=Yuichi Nogi |author4=Yuka Nakamura |author5=Jin Tamaoka |author6=Koki Horikoshi |title=Extremely Barophilic Bacteria Isolated from the Mariana Trench, Challenger Deep, at a Depth of 11,000 Meters
|journal=Appl Environ Microbiol
|volume=64
|issue=4
|pages=1510–1513
|date=April 1998
|doi=10.1128/AEM.64.4.1510-1513.1998 |url= |pmid=9546187
|pmc=106178
|bibcode=1998ApEnM..64.1510K }}</ref> These two species of bacteria appear to be obligately barophilic. The optimal pressure conditions for growth of ''S. benthica'' is 70 [[Pascal (unit)|Megapascals (MPa)]], while ''M. yayanosii'' grows best at 80 MPa; no growth at all was detected at pressures of less than 50 MPa with either strain.<ref name=Kato1998/> Both species appear to contain high levels of [[docosahexaenoic acid]] (DHA) and [[eicosapentaenoic acid]] (EPA), [[omega-3 fatty acid]]s which could prove to be useful in the treatment of [[hypertension]] and even [[cancer]].<ref name=Kakuchi/>

In December 1997, ''Kaikō'' located the wreck of ''[[Tsushima Maru]]'' on the sea floor off the coast of [[Okinawa Prefecture|Okinawa]]. ''Tsushima Maru'' was an unmarked Japanese passenger/cargo ship that was sunk during World War II by {{USS|Bowfin|SS-287|6}}, a [[United States Navy]] [[submarine]].

In May 1998, ''Kaikō'' returned again to Challenger Deep, this time collecting specimens of ''[[Gammaridea|Hirondellea gigas]]''. ''Hirondellea gigas'' (Birstein and Vinagradov, 1955) is a [[crustacean]] of the [[Uristidae]] [[family (biology)|family]] of [[marine (ocean)|marine]] [[Amphipoda|amphipods]].<ref>{{ITIS |id=94312 |taxon=Hirondellea |access-date=24 June 2010}}</ref>

In October 1999, ''Kaikō'' performed a robotic mechanical operation at a depth of 2,150 meters off the coast of Okinawa near the [[Ryukyu Trench]], connecting measuring equipment with underwater cables on the sea floor. On this mission, another bacterial species, ''[[Shewanella violacea]]'', was discovered at a depth of 5,110 meters.<ref>{{cite journal
|author1=Yuichi Nogi |author2=C. Kato |author3=Koki Horikoshi |title=Taxonomic studies of deep-sea barophilic Shewanella strains and description of Shewanella violacea sp. nov
|journal=Archives of Microbiology
|volume=170
|issue=5
|pages=331–338
|date=September 1998
|pmid=9818352
|doi=10.1007/s002030050650
|s2cid=22472007 }}</ref> This organism is notable for its brilliant violet-colored [[biological pigment|pigment]]. Certain compounds found in ''S. violacea'' may have applications in the [[cosmetics]] industry (development of products for lightening of skin tone) and also in the [[semiconductor]] industry (development of chemicals to be used in production of semiconductors).<ref name=Kakuchi/>

In late November 1999, ''Kaikō'' located the wreckage of [[H-II|H-2]] No. 8, a [[National Space Development Agency of Japan|NASDA]] rocket ([[launch vehicle|satellite launch system]]), on the sea floor at a depth of 2,900 meters off the [[Bonin Islands|Ogasawara Islands]]. H-2 flight F8 was conducted on 15 November 1999. The rocket, which was carrying a [[Multi-Functional Transport Satellite]] (MTSAT) payload, self-destructed after experiencing an engine malfunction shortly after it was launched.

In August 2000, ''Kaikō'' discovered hydrothermal vents and their associated [[deep sea communities]] at a depth of 2,450 meters near the [[Central Indian Ridge]]. The Central Indian Ridge is a [[divergent boundary|divergent]] [[Plate tectonics|tectonic plate]] [[Plate boundaries#Types of plate boundaries|boundary]] between the [[African Plate]] and the [[Indo-Australian Plate]] located in the western [[Indian Ocean]].

On 29 May 2003, ''Kaikō'' was lost at sea during [[2003 Pacific typhoon season#Typhoon Chan-hom|Typhoon Chan-Hom]], when a steel secondary cable connecting it to its launcher at the surface broke off the coast of [[Shikoku|Shikoku Island]].<ref name=Ishibashi2008/>

In May 2004, JAMSTEC resumed its research operations, using a converted ROV as its vehicle. The ROV, formerly known as ''UROV 7K'', was rechristened ''Kaikō7000II''. The ''7000'' designation indicates that this vessel is rated for diving to a maximum depth of 7,000 meters.

==Development of ABISMO==
{{Main|ABISMO}}
While the temporary replacement ROV (''Kaikō7000II'') has a remarkable performance record, it is only rated to 7,000 meters and cannot reach the deepest oceanic trenches. For this reason, JAMSTEC engineers began work on a new 11,000-meter class of ROV in April 2005.<ref name=Ishibashi2008>{{cite journal
 |author1=Shōjirō Ishibashi 
 |author2=Hiroshi Yoshida 
 |title=Developing a Sediment Sampling ROV for the Deepest Ocean 
 |journal=Sea Technology 
 |date=March 2008 
 |url=http://findarticles.com/p/articles/mi_qa5367/is_200803/ai_n25418957/ 
 |access-date=27 June 2010 
}}{{dead link|date=May 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><ref name=Itoh2008>{{cite book
 |author1=Kazuaki Itoh 
 |author2=Tomoya Inoue 
 |author3=Junichiro Tahara 
 |author4=Hiroyuki Osawa 
 |author5=Hiroshi Yoshida 
 |author6=Shōjirō Ishibashi 
 |author7=Yoshitaka Watanabe 
 |author8=Takao Sawa 
 |author9=Taro Aoki 
 |title=Proceedings of the Eighth (2008) ISOPE Pacific/Asia Offshore Mechanics Symposium 
 |chapter=Sea Trials of the New ROV ABISMO to Explore the Deepest Parts of Oceans 
 |publisher=The International Society of Offshore and Polar Engineers 
 |location=Bangkok, Thailand 
 |date=10–14 November 2008 
 |pages=1 
 |isbn=978-1-880653-52-4 
 |chapter-url=http://www.isope.org/publications/proceedings/ISOPE-PACOMS/PACOMS2008/papers/P08-57itoh.pdf 
 |access-date=27 June 2010 
 |url-status=dead 
 |archive-url=https://web.archive.org/web/20111004094404/http://www.isope.org/publications/proceedings/ISOPE-PACOMS/PACOMS2008/papers/P08-57itoh.pdf 
 |archive-date= 4 October 2011 
}}</ref> The project is called ''ABISMO'' (Automatic Bottom Inspection and Sampling Mobile), which translates to ''abyss'' in Spanish. Initial sea trials of ''ABISMO'' were conducted in 2007. The craft successfully reached a planned depth of 9,760-meters, the deepest part of [[Izu–Ogasawara Trench]], where it collected core samples of sediment from the seabed.<ref name=Ishibashi2008/><ref name=Itoh2008/>

==See also==

* {{annotated link|Mir (submersible)|''MIR''}}
* {{annotated link|DSV Shinkai|''Shinkai''}}
* {{annotated link|Explorer AUV|''Explorer''}}
* {{annotated link|Nereus (underwater vehicle)|''Nereus''}}
* {{annotated link|ABISMO|''ABISMO'' ROV}}
* {{annotated link|Autonomous underwater vehicle}}
* {{annotated link|Bathymetry}}
* {{annotated link|Deep sea}}
* {{annotated link|Deep-submergence vehicle}}
* {{annotated link|Diving chamber}}
* {{annotated link|Timeline of diving technology}}

==References==
{{reflist}}

==Further reading==
{{Refbegin|colwidth=30em}}
*{{cite journal
|author=Takai, K., A. Inoue and K. Horikoshi
|title=Thermaerobactor Marianensis gen. nov., sp. nov., an Aerobic Extremely Thermophilic Marine Bacterium from the 11,000 Meter-Deep Mariana Trench
|journal=International Journal of Systematic Bacteriology
|volume=49
|issue=2
|pages=619–628
|year=1999
|doi=10.1099/00207713-49-2-619|pmid=10319484
|doi-access=free
}}
{{Refend}}

==External links==
* [http://www.jamstec.go.jp/e/about/equipment/ships/kaiko.html JAMSTEC's Kaikō page]
* [http://marinebio.org/oceans/deep/ Marine Biology: The Deep Sea] – General resource on deep sea creatures
* [http://oceanexplorer.noaa.gov/technology/subs/abe/abe.html Autonomous Benthic Explorer AUV (ABE)]
* [http://www.whoi.edu/oceanus/viewArticle.do?id=70906&sectionid=1002 R.I.P.  A.B.E: The pioneering Autonomous Benthic Explorer is lost at sea]

{{Japan Agency for Marine-Earth Science and Technology vessels and vehicles}}
{{physical oceanography|expanded=other}}
{{Underwater diving|divsup}}

{{authority control}}

{{DEFAULTSORT:Kaiko}}
[[Category:Deep sea fish]]
[[Category:Marine biology]]
[[Category:Research submarines of Japan]]
[[Category:Physical oceanography]]
[[Category:Remotely operated underwater vehicles]]
[[Category:Japan Agency for Marine-Earth Science and Technology]]