soulxtc
August 21st, 2006, 09:01 PM
US astronomers say they have found the first direct evidence for the mysterious stuff called dark matter.
Dark matter - which does not emit or reflect enough light to be "seen" - is thought to make up 25% of the Universe.
By contrast, the ordinary matter we can see is believed to make up no more than about 5% of our Universe.
Until now, astronomers have only been able to infer the existence of this dark material through the gravitational effects it has on ordinary matter.
The researchers have discovered what is effectively the gravitational signature of dark matter.
This signature was created by dark matter and ordinary matter being wrenched apart by the immense collision of two large galaxy clusters.
http://news.bbc.co.uk/2/hi/science/nature/5272226.stm?ls
http://newsimg.bbc.co.uk/media/images/41998000/jpg/_41998472_dark_nasa_203.jpg
Dark matter - which does not emit or reflect enough light to be "seen" - is thought to make up 25% of the Universe.
By contrast, the ordinary matter we can see is believed to make up no more than about 5% of our Universe.
Until now, astronomers have only been able to infer the existence of this dark material through the gravitational effects it has on ordinary matter.
The researchers have discovered what is effectively the gravitational signature of dark matter.
This signature was created by dark matter and ordinary matter being wrenched apart by the immense collision of two large galaxy clusters.
http://news.bbc.co.uk/2/hi/science/nature/5272226.stm?ls
http://newsimg.bbc.co.uk/media/images/41998000/jpg/_41998472_dark_nasa_203.jpg