UH Manoa research vessel has part in deep-sea robotic vehicle reaching deepest part of ocean

University of Hawaiʻi at Mānoa
Posted: Jun 5, 2009

A new type of deep-sea robotic vehicle called Nereus has successfully reached the deepest part of the world‘s ocean, reports a team of U.S. engineers and scientists aboard the University of Hawaiʻi at Mānoa research vessel Kilo Moana. The dive to 10,902 meters (6.8 miles) occurred on May 31, 2009, at the Challenger Deep in the Mariana Trench in the western Pacific Ocean.

The dive makes Nereus the world‘s deepest-diving vehicle and the first vehicle to explore the Mariana Trench since 1998.

Nereus‘s unique hybrid-vehicle design makes it ideally suited to explore the ocean‘s last frontiers. The unmanned vehicle is remotely operated by pilots aboard a surface ship via a lightweight, micro-thin, fiber-optic tether that allows Nereus to dive deep and be highly maneuverable. Nereus can also be switched into a free-swimming, autonomous vehicle.

The expedition left Guam aboard RV Kilo Moana on May 24 to begin a two-week engineering test cruise. On May 25, the team, which includes co-principal investigators Louis Whitcomb, a professor of engineering at The Johns Hopkins University, and Dana Yoerger of WHOI who were responsible for development of the vehicle‘s navigation and control system, conducted a planned sequence of successively deeper dives—testing Nereus, making scientific observations and collecting deep-sea samples at each depth they reached. Testing continued over the next few days, and the team was to have returned to port on June 5.Co-chief scientists of the expedition, Tim Shank, a WHOI biologist, and Patty Fryer, a geologist with the University of Hawaiʻi at Mānoa, were on board to examine the samples retrieved by the vehicle during each dive in its ROV mode. On its dive to the Challenger Deep, Nereus spent over 10 hours on the bottom, sending live video back to the ship through its fiber-optic tether and collecting geological and biological samples with its manipulator arm, and placed a marker on the seafloor signed by those onboard the surface ship. "The samples collected by the vehicle include sediment from the subducting and overriding tectonic plates that meet at the trench and, for the first time, rocks from deep exposures of the Earth‘s crust close to mantle depths south of the Challenger Deep," said Fryer. "We will know the full story once the shore-based analyses are completed back the laboratory this summer and integrate them with the new mapping data to tell a story of plate collision in greater detail than ever before accomplished in the worlds oceans."The design and construction of Nereus has been documented since 2006 by the Science Channel. Their cameras were aboard the Kilo Moana for this historic expedition to the deepest waters on Earth, chronicling the team‘s tests and findings for American audiences. A one-hour documentary produced by Discovery Studios will air on Science Channel and Science Channel HD early this fall.

For more information, visit: http://soest.hawaii.edu