article_snippet: Researchers have mapped dark matter in several colliding galaxy clusters more than a billion light-years away.
article_snippet: Clockwise from top left, the galaxy clusters are: MACS J0416.1+2403, MACS J0152.5+2852, MACS J0717.5+3745, ZwCl 1358+62, Abell 2744 and Abell 370 .
article_snippet: scientists from the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland, the University of Edinburgh and Durham University used data from the Hubble Space Telescope and the Chandra X-ray Observatory to measure galaxy clusters - collections of hundreds of galaxies.
article_snippet: ‘particles’ may simply pass through each other when galaxy clusters collide.
article_snippet: ‘This work looks at the way dark matter interacts with This work when massive clouds of This work are smashed together with other massive clouds,’ lead author
article_snippet: When physicists study the dynamics of galaxies and the movement of stars, physicists are confronted with a mystery.
article_snippet: Dr Harvey's data came from the Chandra X-ray Space Observatory and the Hubble telescope, and included the famous Bullet Cluster collision (shown), a collision of two galaxy clusters whose gas has been molded into the shape of a bullet.
article_snippet: ’ the researchers also used data from the Chandra X-ray Observatory (illustration shown) to measure dark matter in the distant galaxies.
article_snippet: Shown is the galaxy cluster 
article_snippet: MACS J0416.1+2403 and its dark matter distribution, shown in blue, based on its gravitational interactions .
article_snippet: In addition, dark matter speeds up the motion of galaxies inside galaxy clusters, which are collections of hundreds of galaxies, containing literally astronomical amounts of stars, planets, and gases.
article_snippet: Galaxy clusters are also 90 per cent dark matter, which makes Galaxy clusters ideal for studying it, especially when Galaxy clusters collide into each other and force Galaxy clusters respective dark matters to interact.
article_snippet: Based on this knowledge, Dr Harvey and his colleagues studied data from 72 galaxy cluster collisions.
article_snippet: These cosmic crashes happen over the course of billions of years when galaxy clusters attract each other because of These cosmic crashes gargantuan masses.
article_snippet: When this happens, the dark matter in each galaxy cluster interacts with that of the other, offering a unique opportunity to study it.
article_snippet: The team's data came from the Chandra X-ray Space Observatory and the Hubble telescopethe Hubble telescope, and included the famous Bullet Cluster collision, a collision of two galaxy clusters whose gas has been molded into the shape of a bullet.