In pictures: Marathon dive to the bottom of the Mariana Trench finds new species of isopod

In a 12-hour round trip, the Limiting Factor travelled 11km below sea level and discovered a previously unknown species of crustacean.

Published: April 25, 2021 at 11:00 pm

On Friday 5 March, Hamish Harding and Victor Vescovo were sealed into Limiting Factor, a two-person submersible, to begin their descent to Challenger Deep – the deepest section of the Mariana Trench, located close to 11km below the surface of the Pacific Ocean.

The pair spent almost 12 hours making the round trip to the bottom and back.

The Deep Submergence Vehicle Limiting Factor © Action Aviation
© Action Aviation

The Deep Submergence Vehicle (DSV) Limiting Factor begins its dive. Encased within its outer body is a near-spherical pressure hull made of 90mm thick titanium, needed to withstand the crushing pressure over a thousand times greater than at sea level. It’s one of the few crewed vehicles capable of repeated dives to full ocean depth (11km).

Hamish Harding (left) and Victor Vescovo © Action Aviation
© Action Aviation

Hamish Harding (left) takes a selfie sitting beside Limiting Factor’s pilot Victor Vescovo, as the pair descend into Challenger Deep.

Robotic support vehicle collecting isopods © Action Aviation
© Action Aviation

The arm of the CLOSP lander (one of Limiting Factor’s three robotic support vehicles) collects unidentified isopods at a depth of 10,925m.

A selection of the isopods collected by the mission © Action Aviation
© Action Aviation

The isopods were brought back to the surface and analysed aboard Limiting Factor’s mothership Deep Submersible Support Vessel (DSSV) Pressure Drop. Early indications suggest they’re a previously unknown species of the crustacean.

The seabed at Challenger Deep © Action Aviation
© Action Aviation

During their 12-hour dive, Harding and Vescovo spent four-and-a-quarter hours at the bottom of Challenger Deep, covering a distance of 4km along the undulating and silt-covered sea bed.

Hamish Harding climbing out of the DSV © Action Aviation
© Action Aviation

Hamish Harding emerges from DSV Limiting Factor after its safe return to the surface.

See more science photo galleries: