On March 26 at 7:52am local time, film maker/explorer James Cameron entered the history books and became the first person to visit the ocean's deepest point alone. Just two weeks ago, we reported on his previous solo-dive record of 26,791 feet (8,166m), which he handily smashed by plunging 35,756 feet (10,898m) into the Mariana Trench's Challenger Deep southwest of Guam. If the handful of contenders still vying for the record want to beat Cameron, they'll now have to excavate, because that's as deep as it gets.

The nearly 7-mile (10.9km) dive was made possible by the Deepsea Challenger, a specially-designed submersible nearly eight years in the making. The long, thin vehicle, which Cameron calls a "vertical torpedo," bristles with lights, cameras, powerful thrusters and is oriented with the cramped pilot sphere at the bottom. It drops straight down sphere first, rather than horizontally, like most deep-diving subs.

Several hours before launch, the support team dropped an unmanned vehicle about the size of a phone booth into the trench in an effort to attract whatever might be living down there. "I'm going to attempt to rendezvous with that vehicle so I can observe animals that are attracted to the chemical signature of its bait," Cameron told National Geographic. When he finally reached bottom, he sent the anxious crew on the support vessel Mermaid Sapphire the welcome message: "All systems OK."

To take advantage of his up to six hours in the trench and hopefully make some valuable contributions to science, Cameron will pilot the sub to a variety of different environments including nearby cliffs. "I'll be doing a bit of a longitudinal transect along the trench axis for a while, and then I'll turn 90 degrees and I'll go north and work myself up the wall," he said. He'll also be able to use the sub's manipulator arm to gather samples for the eager scientists waiting up above.

"The deep trenches are very poorly understood by science," Cameron explained. "They're really the last frontier of exploration here on planet Earth because human beings have not gone down there and looked, so we're going to go down there with our cameras and with our lights and we're going to find the answers to some of those questions."

The dive is still in progress at this writing, so stay tuned for more news when Cameron returns from the bottom.

Source: DeepSea Challenge, National Geographic