An international team of researchers from Japan, Taiwan, and the United Kingdom has provided the first direct and clear evidence for an extremely flattened shape of dark matter's distribution in massive clusters of galaxies, a finding that confirms a major prediction of the prevailing dark matter model. The researchers took advantage of the gravitational lensing effect to make detailed measurements of the spatial distributions of dark matter in 20 massive clusters of galaxies. A thorough examination of the shape of dark matter's distribution in the cosmos may open up a new way to explore the nature of this enigmatic matter.

One approach to a solution is to make detailed measurements of the spatial distribution of dark matter and then compare the data to predictions drawn from theoretical models. Both aspects of this approach have their difficulties. How can the distribution of dark matter be measured? What are plausible assumptions to include in models of dark matter?

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More info: Subaru telescope web page