“Exploring Earth’s Ocean” timeline highlights key moments in ocean exploration—ranging from mapping the seafloor, the evolving technology, and the depths explored. These points in time date back to 332 BC, where Alexander the Great used divers to remove underwater obstacles. The timeline ends in 2012 with James Cameron’s solo dive into the Mariana Trench—marking the first solo dive in history. The journey of ocean exploration continues until this day, with only 20% of it uncovered.
The timeline was created using Northwestern University’s Knight Lab Timeline resource.
The image comparison below shows the evolution of the manned submersible; previously known as the bathysphere. On the left William Beebe (pictured) and his partner Otis Barton were lowered in this tethered bathysphere to a depth of 3,028 meters—marking the first manned exploration of the sea. On the right, James Cameron is pictured inside a model of the Deepsea Challenger submersible. In 2012 Cameron goes on the world’s first solo mission to the Mariana Trench, to a depth of 6.8 miles.
The image comparison was created using Northwestern University’s Knight Lab Juxtapose resource.