Scotland and the Antarctic

Section 7: The legacy of Bruce ... Environmental Problems

Lake Vostok

The Russian base at Vostok lies 1,000 kilometres (620 miles) from the sea and 1,000 kilometres from the South Pole. It was established in 1957. In 1983 the lowest temperature on Earth was recorded here: -89.3°C.

In 1974, a British team flying over Vostok base was mapping the topography. The radar image suddenly went flat and they thought they must be flying over water. No further research was done.

In the 1990s satellite data revealed a huge flat area near Vostok base and in the same area as the early radar images. There was a huge lake under the ice, and this became known as Lake Vostok.

Lake Vostok is 200km (125 miles) long, 50km (30 miles) wide and half a kilometre (one-third of a mile) deep and is under four kilometres (two-and-a-half miles) of ice. With an area of 14,000 square kilometres it is one of the top ten largest lakes in the world.

The Russians had been drilling down towards the lake for 3,623 metres (11,800ft) producing the longest ice core ever extracted. They stopped 120 metres (390ft) short of the lake to avoid contamination. At that depth huge ice crystals were found over a metre long. Ice drilling uses antifreeze and kerosene (paraffin), so this was stopped to prevent the lake becoming contaminated by chemicals or any microbes that might be attached to the drill head.

The American space agency NASA is working on a special drill which would use heat to penetrate the lake and send back pictures via a fibre-optic cable. There may be primitive life forms in the lake despite the mean summer temperature of -35°C on the surface. The intention is to test-drill on one of the 70 smaller subglacial lakes discovered in the Antarctic. Any techniques developed may be used at a later date to drill through the ice-covered surface of Jupiter's moon, Europa.

Lake Vostok is thought to be at least 500,000 years old and may be millions of years old.