1988 – RV Moana Wave – On 22 August 1988, the U.S. Navy-owned 1,000-ton research vessel Moana Wave (AGOR-22), operated by the Hawaii Institute of Geophysics (HIG), University of Hawaii, under the direction of chief scientist Robert C. Thunell from the University of South Carolina, transited northwesterly across the central basin of the Challenger Deep, conducting a single-beam bathymetry track by their 3.5 kHz narrow (30-degs) beam echosounder with a Precision Depth Recorder. In addition to sonar bathymetry, they took 44 gravity cores and 21 box cores of bottom sediments. The deepest echosoundings recorded were 10,656 metres (34,961 ft) to 10,916 metres (35,814 ft), with the greatest depth at 11°22′N 142°25′E in the central basin.[13] This was the first indication that all three basins contained depths in excess of 10,900 metres (35,800 ft).