How We Found World’s Deepest Fish in the Mariana Trench—and Why We Must Keep Exploring

A diver wearing a Santa Claus outfit feeds fish inside a tank at the Aquaria KLCC in Kuala Lumpur on Dec. 16, 2014. Manan Vatsyayana/AFP/Getty Images

It was our 14th expedition to the trenches of the Pacific Ocean, where depths can exceed 10,000 meters (32,808 feet). And it was due to be our last for the foreseeable future.

We had been aboard the Schmidt Ocean Institute’s (SOI) vessel RV Falkor for 30 days. It was almost over. Then, it turned out to be “the big one.”