Editing Challenger Deep (section)

===2010 – USNS ''Sumner''===
On 7 October 2010, further sonar mapping of the Challenger Deep area was conducted by the US [[Center for Coastal & Ocean Mapping]]/Joint Hydrographic Center (CCOM/JHC) aboard the 4.762-ton [[USNS Sumner (T-AGS-61)|''Sumner'']]. The results were reported in December 2011 at the annual [[American Geophysical Union]] fall meeting. Using a Kongsberg Maritime EM 122 multi-beam echosounder system coupled to positioning equipment that can determine latitude and longitude up to {{convert|50|cm|in|abbr=on}} accuracy, from thousands of individual soundings around the deepest part the CCOM/JHC team preliminary determined that the Challenger Deep has a maximum depth of {{convert|10994|m|ft|abbr=on}} at {{Coord|11.326344|N|142.187248|E|scale:100000}}, with an estimated vertical uncertainty of ±{{convert|40|m|ft|0|abbr=on}} at two [[standard deviation]]s (i.e. ≈ 95.4%) confidence level.<ref name=BBC_CCOM>{{cite news |last= Amos |first= Jonathan |title= Oceans' deepest depth re-measured |url= https://www.bbc.co.uk/news/science-environment-15845550 |date= 7 December 2011 |work= BBC News |access-date= 7 December 2011 |archive-date= 2 December 2021 |archive-url= https://web.archive.org/web/20211202205859/https://www.bbc.co.uk/news/science-environment-15845550 |url-status= live }}</ref> A secondary deep with a depth of {{convert|10951|m|ft|abbr=on}} was located at approximately {{convert|23.75|nmi|km|1|abbr=on}} to the east at {{Coord|11.369639|N|142.588582|E|scale:100000}} in the eastern basin of the Challenger Deep.<ref name="2011 cruise report">{{cite web|url=http://ccom.unh.edu/sites/default/files/publications/Armstrong_2011_cruise_report_SU10-02_Marianas.pdf |archive-url=https://web.archive.org/web/20120526180857/http://ccom.unh.edu/sites/default/files/publications/Armstrong_2011_cruise_report_SU10-02_Marianas.pdf |archive-date=2012-05-26 |url-status=live |publisher=NOAA/UNH Joint Hydrographic Center University of New Hampshire |title=Cruise Report – UNH-CCOM/JHC Technical Report 11-002 |first=Andrew A. |last=Armstrong |page=12 |date=22 December 2011 |access-date=1 May 2012}}</ref><ref>{{cite web| url = http://www.km.kongsberg.com/ks/web/nokbg0240.nsf/AllWeb/01FB0F22974EA50FC125715E002B2143?OpenDocument| title = EM 122 Multibeam echosounder| access-date = 26 February 2013| archive-date = 6 November 2018| archive-url = https://web.archive.org/web/20181106235126/https://www.km.kongsberg.com/ks/web/nokbg0240.nsf/AllWeb/01FB0F22974EA50FC125715E002B2143?OpenDocument| url-status = live}}</ref><ref>{{cite web|url=http://www.km.kongsberg.com/ks/web/nokbg0397.nsf/AllWeb/E016DF00EBFC2964C12571B1003F9DDA/$file/306105aa_em122ds_lr.pdf?OpenElement|title=EM 122 sonar multibeam bathymetry system brochure|website=kongsberg.com|access-date=26 February 2013|archive-date=30 September 2021|archive-url=https://web.archive.org/web/20210930093430/https://www.kongsberg.com/km.kongsberg.com/ks/web/nokbg0397.nsf/AllWeb/E016DF00EBFC2964C12571B1003F9DDA/$file/306105aa_em122ds_lr.pdf?OpenElement|url-status=dead}}</ref><ref>[http://www.ldeo.columbia.edu/res/pi/MB-System/formatdoc/EM_Datagram_Formats_RevP.pdf?OpenElement Instruction manual EM Series (EM 120 & EM 122) Multibeam echo sounders] {{webarchive|url=https://web.archive.org/web/20140102191111/http://www.ldeo.columbia.edu/res/pi/MB-System/formatdoc/EM_Datagram_Formats_RevP.pdf?OpenElement |date=2 January 2014}}</ref>