Page "Challenger Deep" Paragraph 3

June 2009 sonar mapping of the Challenger Deep by the Simrad EM120 ( sonar multibeam bathymetry system for 300 – 11, 000 m deep water mapping ) aboard the RV Kilo Moana indicated a depth of.

The sonar system uses phase and amplitude bottom detection, with a precision of better than 0. 2 % of water depth ; this is an error of about at this depth.

Further soundings made by the US Center for Coastal & Ocean Mapping in 2011 are in agreement with this figure, placing the deepest part of the Challenger Deep at, with a vertical precision of approximately.