Washington: A team of astronomers from Taiwan, England, and Japan have used the Subaru Telescope to measure the distribution of dark matter in fifty galaxy clusters and found that its density gradually decreases from the center of these cosmic giants to their diffuse outskirts.
This new evidence about the mysterious dark matter that pervades our universe conforms to the predictions of cold dark matter theory, known as "CDM."
Few scientists seriously doubt the existence of dark matter, which researchers discovered almost eighty years ago.
Nevertheless, astronomers cannot directly see dark matter in the night sky, and particle physicists have not yet identified a dark matter particle in their experiments.
"What is dark matter?" is a big unanswered question facing astronomers and particle physicists, especially because invisible dark matter probably makes up 85 percent of the mass of the universe.
The current team, led by Dr. Nobuhiro Okabe (Academia Sinica, Taiwan) and Dr. Graham Smith (University of Birmingham, England), used the Subaru Prime Focus Camera (Suprime-Cam) to investigate the nature of dark matter by measuring its density in fifty galaxy clusters, the most massive objects in the universe.
The team wanted to use a large sample of galaxy clusters to find out how the density of dark matter changes from the center of a typical galaxy cluster to its outskirts.