Feeds

Robosub prowls Pacific's hadal depths

Nereus plunges to 10,902 metres

Top 5 reasons to deploy VMware with Tegile

US scientists are hailing a "new era" of deep-sea exploration after successfully dispatching a robotic vehicle to the bottom of the Mariana Trench - 10,902 metres or 6.8 miles beneath the Pacific's surface.

The Nereus (pictured below during tests off Hawaii in 2007) hit the bottom of the Challenger Deep on Sunday, making it the only the third vehicle to probe the profoundest hadal depths. In 1960, Jacques Piccard and Don Walsh aboard bathyscaphe Trieste descended to 10,911 metres.

Nereus during trials off Hawaii in 2007. Pic: WHOI

Between 1995 and 1998, the Japanese-built unmanned Kaiko made three dives in the trench, but was lost at sea in 2003, marking a temporary end to exploration of the Pacific's deepest point.

Until now. The three-ton Nereus was lowered from the research vessel Kilo Moana, braving pressures greater than 1,000 times that at Earth’s surface, or "crushing forces similar to those on the surface of Venus", during its ten-hour stay on the bottom. It collected samples and "placed a marker on the seafloor signed by those onboard the surface ship".

In designing Nereus, scientists and engineers from the Woods Hole Oceanographic Institution (WHOI) balanced "size, weight, materials cost, and functionality" to create a hybrid vehicle capable of withstanding its extreme operating environment without costing the GNP of a small country.

WHOI explains: "Building on previous experience developing tethered robots and autonomous underwater vehicles at WHOI and elsewhere, the team fused the two approaches together to develop a hybrid vehicle that could fly like an aircraft to survey and map broad areas and then be converted at sea into a tethered, remotely operated vehicle (ROV) that can hover like a helicopter near the seafloor to conduct experiments or to collect biological or rock samples under real-time human control."

The result is a vehicle powered by 4,000 onboard lithium-ion batteries ("similar to those used in laptop computers and cell phones"), and boasting around 800 weight-saving ceramic floation spheres (as opposed to the "much heavier traditional syntactic foam" used on previous submersibles), and a hydraulically-operated robotic manipulator arm modified to use as little of its vital battery power as possible.

Removing the need to provide external power has allowed WHOI to deploy a revolutionary tethering system. It elaborates: "Traditional robotic systems use a steel-reinforced cables containing copper wires to power the vehicle and optical fibers to enable information to be passed between the ship and the vehicle. If such a cable were used to reach the seafloor in the Mariana Trench, it would snap under its own weight."

Nereus, though, is attached to the surface by nothing more than a tether the diameter of a human hair, "composed of glass fiber core with a very thin protective jacket of plastic" and with a breaking strain of just 4kg (8.8lb).

So slight is the tether that 40km (25 miles) of the cable are dispensed from "two canisters the size of large coffee cans".

Scientists have high hopes that Nereus will enable new insights into the murky depths, and Julie Morris, director of the National Science Foundation Ocean Sciences Division - which stumped much of the cash for the $8m project - concluded: “Much of the ocean’s depth remains unexplored. Ocean scientists now have a unique tool to gather images, data, and samples from everywhere in the oceans, rather than those parts shallower than 6,500 metres.

"With its innovative technology, Nereus allows us to study and understand the ocean’s deepest regions, previously inaccessible. We’re very pleased with the success of these sea trials.” ®

Bootnote

For those of you disappointingly not up to speed on Greek mythology, Nereus was the son of Pontus and Gaea (Gaia, if you will), and "had the gift of prophecy and could change himself into any shape".

He had 50 kids by fellow sea deity Doris, although the family mostly hung around the Aegean, rather then the Pacific. More here.

Top 5 reasons to deploy VMware with Tegile

More from The Register

next story
Renewable energy 'simply WON'T WORK': Top Google engineers
Windmills, solar, tidal - all a 'false hope', say Stanford PhDs
SEX BEAST SEALS may be egging each other on to ATTACK PENGUINS
Boffin: 'I think the behaviour is increasing in frequency'
Post-pub nosh neckfiller: The MIGHTY Scotch egg
Off to the boozer? This delicacy might help mitigate the effects
I'M SO SORRY, sobs Rosetta Brit boffin in 'sexist' sexy shirt storm
'He is just being himself' says proud mum of larger-than-life physicist
NASA launches new climate model at SC14
75 days of supercomputing later ...
Britain's HUMAN DNA-strewing Moon mission rakes in £200k
3 days, and Kickstarter moves lander 37% nearer takeoff
Simon's says quantum computing will work
Boffins blast algorithm with half a dozen qubits
prev story

Whitepapers

Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.
Internet Security Threat Report 2014
An overview and analysis of the year in global threat activity: identify, analyze, and provide commentary on emerging trends in the dynamic threat landscape.
Top 5 reasons to deploy VMware with Tegile
Data demand and the rise of virtualization is challenging IT teams to deliver storage performance, scalability and capacity that can keep up, while maximizing efficiency.