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Distribution of dark matter revealed by faint starlight in Hubble images

Astronomers have employed a revolutionary method to detect dark matter in galaxy clusters. The method allows astronomers to 'see' the distribution of dark matter more accurately than any other method used to date and it could possibly be used to explore the ultimate nature of dark matter.



Astronomers using data from the NASA/ESA Hubble Space Telescope have employed a revolutionary method to detect dark matter in galaxy clusters. The method allows astronomers to "see" the distribution of dark matter more accurately than any other method used to date and it could possibly be used to explore the ultimate nature of dark matter.


The results were published in the journal Monthly Notices of the Royal Astronomical Society.

In recent decades astronomers have tried to understand the true nature of the mysterious substance that makes up most of the matter in the Universe, dark matter, and to map its distribution in the Universe. Now two astronomers from Australia and Spain have used data from the Frontier Fields programme of the NASA/ESA Hubble Space Telescope to accurately study the distribution of dark matter.

Intracluster light is a byproduct of interactions between galaxies

Intracluster light is a byproduct of interactions between galaxies. In the course of these interactions, individual stars are stripped from their galaxies and float freely within the cluster. Once free from their galaxies, they end up where the majority of the mass of the cluster, mostly dark matter, resides.


Both the dark matter and these isolated stars, which form the intracluster light, act as collisionless components. These follow the gravitational potential of the cluster itself. The study showed that the intracluster light is aligned with the dark matter, tracing its distribution more accurately than any other method relying on luminous tracers used so far.


This method is also more efficient than the more complex method of using gravitational lensing. While the latter requires both accurate lensing reconstruction and time-consuming spectroscopic campaigns, the method presented here utilises only deep imaging. This means more clusters can be studied with the new method in the same amount of observation time. The results of the study introduce the possibility of exploring the ultimate nature of dark matter


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#DarkMatter #Hubble #Space #Universe