Isis, a van-sized bundle of high-technology, is the UK's first deep-sea ROV (Remote Operated Vehicle). It can withstand enormous pressure.

Ten kilometres of cable connect it to its "mother ship", allowing scientists to control the vehicle and receive data in real-time.

On the ROV are lights, cameras, sonars and two remotely controlled manipulator arms.

ISIS has allowed researchers for the first time to view previously hidden features up to 5km (3 miles) deep in the Nazare Canyon. The canyon extends out into the eastern Atlantic from the seaside town of Nazare, north of Lisbon. (Above is a 3D computer image of Nazare Canyon.)

On this expedition, the robot is operated from the UK's new research vessel, RRS (Royal Research Ship) James Cook.

In the control room, a team manoeuvres the robot down into the dark; the high-definition cameras captured sights no one expected.

According to the lead scientist, the scientific community had been divided on whether a canyon this deep would be a biological hotspot or an underwater desert. In fact, he says: "It's a mixture of both - some areas like the walls are as active as a coral reef, while others are dominated by sand dunes with no signs of life." Less than 5% of the world's sea-bed has so far been surveyed with modern technology.

Researchers intended to uncover more about the effects of glaciers on the ocean floor and also find out about the animals that inhabit these waters.

The mission lasted for about three weeks from mid-January.  The ROV was placed aboard the British Antarctic Survey's ship - the RSS James Clark Ross - ready to explore.

Isis is able to investigate in fine detail the sea-floor sediments, which have been delivered to Marguerite Bay by the massive ice-sheets that covered the bay about 20,000 years ago. The environmental history of the Antarctic is held in these sediments. This will help the researchers better understand the record of past glacial activity in the Antarctic.

Ancient "meltwater channels", carved into the bed rock, were created thousands of years ago when sea ice extended much further out from land. The steep sides of the meltwater channels observed were covered in diverse fauna. Filter feeders, such as vase sponges, brittle stars and lamp shells can be seen here clinging to the rocky wall.

This multi-armed starfish, measuring an impressive 30cm (1ft) across, was also found as Isis explored the meltwater channels, at depths of 600m (2,000ft).

This five-armed starfish measures about 0.5m (1.6ft) across on the sea-bed floor. To the right, a fish can be seen darting past.