Bathyscaphe Trieste
On 23 January 1960, she reached the ocean floor in the Challenger Deep (the deepest southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh. This was the first time a vessel, manned or unmanned, had reached the deepest known point of the Earth's oceans. The onboard systems indicated a depth of , although this was revised later to ; fairly recently, more accurate measurements have found Challenger Deep to be between and deep.
J. Val Klump
Jeffrey Val Klump is an American limnologist. He was the first person to reach the deepest spot in Lake Superior, a depth of 1333 feet (733 feet below sea level), the second lowest point in the United States after Iliamna Lake, on July 30, 1985 while aboard the R/V Seward Johnson with the Johnson Sea Link-II submersible. Klump was also the first person to reach to the deepest point in Lake Michigan as part of the same expedition. He is currently a professor and dean at the School of Freshwater Sciences at the University of Wisconsin–Milwaukee in Milwaukee, Wisconsin.