It's been a half century since humans have been to the deepest part of the planet, the Pacific Ocean's Marianas Trench at a depth of 35,797 feet. It's only two visitors included Jacques Piccard and Navy Lieutenant Don Walsh in the Trieste Bathyscaphe. That lonely company has increased by one with the addition of James Cameron, famous and rich for his movies such as Terminator 2, Titanic and Avatar, as part of the Deep Sea Challenge. After a 2.5 hour descent, Cameron spent a few hours in the deep exploring before ascending. The extreme pressures at the depth reach 16,000 psi and actually shrunk the diving craft by nearly three inches. Prior to his descent, Cameron commented, "Yeah, of course I'm worried. Worry is a good thing when you're an explorer. I think when you're cavalier, when you take risk for granted—that's when you're going to get bitten." Before making the dive, he put the craft through its paces with a test at 26,000 feet (about 10,000 shallower) with former Trieste driver Walsh advising him.

As an added bit of trivia, Cameron is now credited (by proxy) with having made the world's deepest Tweet sending "Just arrived at the ocean's deepest pt. Hitting bottom never felt so good. Can't wait to share what I'm seeing w/ you @DeepChallenge" from the bottom of the trench. Naturally, its near impossible without ELF receivers for submarines to even communicate submerged let alone more than six miles down. He had a buddy send the message for him by proxy.