Astronomers Shed Light on Secrets of 'Dark Matter'
Oliver Duff
Independent, UK
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British astronomers have come a step closer to understanding one of the most mysterious substances in the universe - the "dark matter" which acts as a kind of cosmic glue, holding galaxies together. New research into dark matter, believed to make up 23 per cent of the cosmos compared to the 4 per cent of "normal matter" that can be seen and felt, has for the first time pinned down its behaviour and properties, which are essential to anchoring an ordered universe.
Scientists assumed the existence of dark matter in the 1930s after "weighing" galaxies and finding that the sum of each galaxy's parts was much less than its total mass.
Scientists have speculated ever since on what the "missing mass" might be. A team led by Professor Gerry Gilmore from Cambridge University's Institute of Astronomy began the latest experiment three years ago in northern Chile's spectacular Atacama desert.
Using an array of interconnected 26ft-wide telescopes the astronomers claim to have achieved astonishing results."We've got the first clue as to what dark matter is," Professor Gilmore. "Which is that you only find this stuff in big, magical, rather dilute lumps, about 1,000 light years across, 40 million times the mass of the Sun." However, he admitted:
"We don't know how to interpret this clue yet."Dark matter does not give off any light, hence its name. Scientists had always assumed that because it couldn't be seen it was "cold" - a sort of dead, sluggish cosmic sludge. But there were two further unexpected findings from the Cambridge research.
The first showed that dark matter actually has a "temperature" higher than that of the surface of the Sun.The second surprise was that particles of dark matter zip about at 9km per second and are loosely packed.
Feb 06, 2006
Oliver Duff
Independent, UK
____________
British astronomers have come a step closer to understanding one of the most mysterious substances in the universe - the "dark matter" which acts as a kind of cosmic glue, holding galaxies together. New research into dark matter, believed to make up 23 per cent of the cosmos compared to the 4 per cent of "normal matter" that can be seen and felt, has for the first time pinned down its behaviour and properties, which are essential to anchoring an ordered universe.
Scientists assumed the existence of dark matter in the 1930s after "weighing" galaxies and finding that the sum of each galaxy's parts was much less than its total mass.
Scientists have speculated ever since on what the "missing mass" might be. A team led by Professor Gerry Gilmore from Cambridge University's Institute of Astronomy began the latest experiment three years ago in northern Chile's spectacular Atacama desert.
Using an array of interconnected 26ft-wide telescopes the astronomers claim to have achieved astonishing results."We've got the first clue as to what dark matter is," Professor Gilmore. "Which is that you only find this stuff in big, magical, rather dilute lumps, about 1,000 light years across, 40 million times the mass of the Sun." However, he admitted:
"We don't know how to interpret this clue yet."Dark matter does not give off any light, hence its name. Scientists had always assumed that because it couldn't be seen it was "cold" - a sort of dead, sluggish cosmic sludge. But there were two further unexpected findings from the Cambridge research.
The first showed that dark matter actually has a "temperature" higher than that of the surface of the Sun.The second surprise was that particles of dark matter zip about at 9km per second and are loosely packed.
Feb 06, 2006
