We departed Tonga yesterday under beautiful skies and cool air. We have 43 souls onboard including three writers and one artist. People are becoming more interested in the Five Deeps project, and we are happy to have them with us to help tell the story of what we have put together and striven to achieve. We are only about a day away from the Horizon Deep, the deepest point in the Tonga Trench.
The ship made a series of detailed sonar runs before the submarine team boarded, and it was determined that the Horizon Deep is definitely not deeper than the Challenger Deep. Given how geologically active this area is – by some accounts the most active trench system in the Pacific – we thought there might be a chance that it was actually deeper. But no, alas, our latest readings indicate the Horizon Deep is 10,820 meters deep. That is 108 meters shallower than the deepest point in the Challenger Deep. They are very close to each other in ultimate depth – within 1% of each other, but the Challenger Deep still rules the deeps.
For now, we are checking out all the systems on the Limiting Factor and planning a potential two-dive series. The first dive, a solo dive by me, would be to the bottom of the Horizon Deep. It has never been visited before by a manned submersible, so that would be a first. On the second dive, I intend on bringing down scientist Heather Stewart of the Royal Geographic Society, to study a massive 2,000′ high underwater wall just east of the Horizon Deep. She is particularly keen to see what geological secrets it might reveal as we do a near-vertical ascent of a wall no one has ever seen. The weather is a bit “sporty” as mariners say, but we are forecasted to have 48 hours of pretty good weather in a day or two’s time. We hope to complete the first back-to-back (one per day for two consecutive days), 10,000-meter dives ever attempted by a sub. Based on the system’s great performance in the Mariana Trench, we believe this is very doable.