Best look yet at invisible dark matter - January 11, 2008
Another story from the American Astronomical Society conference – using the Hubble space telescope researchers have created what they say is the highest resolution map of dark matter ever seen.
Not that you can actually see the dark matter, which is of course invisible. Alex Witze is blogging the conference for Nature over on In the Field:
A team led by Meghan Gray, of the University of Nottingham, and Catherine Heymans, of the University of British Columbia, used gravitational lensing ... to measure how dark matter in space distorts the light from a massive cluster of galaxies known as Abell 901/902. This is a big thing: more than 2.6 billion light-years away, it measures a whopping 16 million light-years across and is composed of more than a thousand galaxies.The concentrations of pink stuff shows where the dark matter lies.
Gravitational lensing involves looking at how light from distant galaxies is bent by the gravitational field of the dark matter around the galaxies. In this case, observing these distortions enabled the reconstruction of the dark matter distribution in the cluster. The new map is claimed to be 2.5 times shaper than a previous (ground-based) survey, and also quite pretty.
“For the first time we are clearly detecting irregular clumps of dark matter in a supercluster. Previous studies were only able to detect fuzzy, circular clumps, but we’re able to resolve detailed shapes that match the distribution of galaxies,” says Heymans.
Further reading
University of British Columbia press release
University of Nottingham press release
Hubble site
News coverage in The Guardian, National Geographic, Wired
More AAS stories on In the Field
Image: detail from dark matter map / NASA, ESA, C. Heymans (University of British Columbia, Vancouver), M. Gray (University of Nottingham, U.K.), M. Barden (Innsbruck), and the STAGES collaboration
Comments
The universe is still expanding because Dark Matter. All the galaxies produce energy, therefore there has to be waste. This waste is Dark Matter. Dark Matter is filling the universe, therefore causing the universe to continue to expand, pushing galaxies further and further away from each other. My thoughts, your thoughts?
Posted by: Oliver Griff | January 12, 2008 07:32 PM