How It Works-Amazing Vehicles

“ A manned submersible needs great compressive

strength to maintain the habitat inside”

LIFE IN THE

TRENCHES

We know very little about life in the deep ocean,

but we do know that in the pitch black at the

bottom, creatures can thrive. Microbes w ith the

capacity to metabolise the hydrogen sulphide

and other compounds that spout from boiling

hydrothermal vents form the base of a food

chain. In turn this attracts deep-ocean

specialised crustaceans, gastropods, worms,

eels and more in a place that was, up until the

Sixties, thought to be uninhabitable. Incredibly,

giant single-cell, amoebic organisms know n as

xenophyophores are found in their greatest

numbers in the oceanic trenches.

Bottom-feeders in the dark regions of the

ocean are usually scavengers, feeding off

whatever falls from the waters above. But much

of the ta xa found in the extremes of the deep

derive their energ y from sources other than the

Sun, in an environment that is analogous to

those found on other planets in the Solar

System. Indeed, extensive studies into these

communities has breathed new hope into

discovering life elsewhere in the cosmos.

Air

The pilot sphere is supplied

with up to 56 hours of oxygen,

while excess carbon dioxide

is scrubbed from the air.

weights are held on the side by
electromagnets. These are dropped

when the pilot needs to rise, but in case
they don’t (thereby marooning the
submersible on the ocean fl oor), a power
failure w ill drop the weights

automatically, the support team on the
surface can trigger the command
themselves and, as a failsafe, a w ire that
helps connect the weights to the

submersible w ill corrode and snap after
13 hours’ exposure to seawater.
In any case, the Deepsea Challenger
uses syntactic foam fl oats, dense enough

to w ithstand the pressure yet lighter
than water – these are able to rapidly lift
the craft back to the surface in just half
the time it took to reach the bottom.

The Deepsea Challenger

The essential difference bet ween a submersible and a submarine

is that a submarine must be able to rec ycle its ow n air and power

supply, while a submersible relies on a support craft on the surface.

This is why military submarines can go for months at sea, while

both the Virgin Oceanic and Deepsea Challenger submersibles

can only support their pilots for a day or so at most.

Xenophyophores are giant single-

celled organisms that live at great

depth, feeding off mineral compounds

Batteries

Hundreds of small lithium

batteries that power the

vessel absorb seawater to

compensate for battery

oil compression.

© NOA A

Cameras

The four bespoke HD

cameras are a tenth of the

size of cameras used in

previous missions.

Pilot sphere

One pilot and all their equipment, as

well as the craft’s instruments, are

crammed into a 109cm (43in)-wide space.

© National Geographic

Thrusters

These control the altitude

of the sub, suspending it

above the ocean floor or

propelling it downward.

DID YOU KNOW? Most of Earth’s ocean floors are 6,000m (19,685ft) deep, which is why subs tend to be rated only to this depth