Scientists have spent decades trying to unveil what’s behind the curtains of dark matter, which was named so because scientists can’t see it other than its gravitational pull in the shape of gravitational waves. It is the only way it was “visible to us.” However, a team of scientists used Hubble Space Telescope’s data to test a revolutionary method for detecting dark matter in galaxy clusters.
Thanks to its gravitational effects, scientists concluded that dark matter makes up about 85% of the universe. The new method for detecting dark matter was captured by NASA’s Hubble Space Telescope, and it uses faint light from rogue stars in the galaxy clusters to reveal the mysterious dark material.
A galaxy cluster is a massive gathering place of various galaxies which are bound by gravitation. Our Milky Way, for example, is located in the Laniakea supercluster which consists of hundreds of thousands of galaxies. The galaxies interact with each other within the cluster and their stars can sometimes even get ripped off and sent floating through the cluster. When the stars wander through the cluster, they can emit a faint light called “intracluster light,” which is what the Hubble captured.
“We have found that very faint light in galaxy clusters, the intracluster light, maps how dark matter is distributed,” Australia’s University of New South Wales Mireia Montes said in a statement, describing the study published in the Monthly Notices of the Royal Astronomical Society.
Before the new method, astronomers had used “gravitational lensing” in order to see how dark matter is distributed across galaxy clusters. Nevertheless, it was too time consuming and required keen eyes for the details. So scientists introduced a new method for detecting dark matter.
The idea was suggested by Montes and the co-author of the study, Ignacio Trujillo of Spain’s Instituto de Astrofisica de Canarias, and it only uses deep-space imaging, which Hubble’s Frontier Fields projects can provide. It can be used to learn about the properties of dark matter in the observed star or galaxy cluster.
However, the gravitational lensing methods were crucial to Montes and Trujillo in discovering the revolutionary method. A previous study used gravitational lensing to look at some six galaxy clusters to study their dark matter properties. Montes and Trujillo then used the new method to see the distribution of the intracluster light and compared it to the previous research.
Their future research will focus on discovering more about the galaxy clusters, particularly the ones which are larger compared to the six already studied. The team will also use an extension to the Hubble Frontier Fields project, the Beyond Ultra-deep Frontier Fields and Legacy Observations.
If the study continues it will allow the new method for detecting dark matter to adapt as a new way of seeing it.