science Update

SUPERSONIC WINDS blowing faster than the speed of sound have been discovered racing around Jupiter. The winds, called auroral electrojets, are composed of electrically charged particles or ions formed by the interaction of the planet's magnetic field and its upper atmosphere.

Steve Miller, an astronomer from University College London, said the winds may explain why the top of the Jovian atmosphere is much warmer than expected for a planet five times more distant from the Sun than the Earth. It is the first time scientists have made direct observations in support of the existence of auroral electrojets.

"Jupiter still has many secrets and many puzzles to solve. Understanding the dynamics of Jupiter is the key to unravelling many of these," Dr Miller said.

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GIANT CRUSTACEANS living in the polar oceans grow bigger than their cousins in warmer seas because of higher levels of oxygen, scientists from the British Antarctic Survey in Cambridge have found. This was thought to be due to lower temperatures, resulting in a slower metabolic rate. However, studies of freshwater crustaceans in Russia found they were twice as large as their salt-water relatives living at the same temperature. "We found that the increased oxygen in the cold oceans and freshwater lakes meant bigger species could be produced," said Professor Lloyd Peck. The work could explain why insects living 300m years ago - when the oxygen content of the atmosphere was 50 per cent greater than today - were giants compared to today's insects.

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A DINOSAUR that lived 210m years ago walked like a turkey, according to scientists from Brown University in Providence, Rhode Island, who used computers to analyse fossilised footprints in Greenland. The theropods, which grew up to seven metres (23ft) long, show similarities to birds in spite of anatomical changes such as the position of the big toe.