Dark matter, a mysterious substance that makes up about 70% of the universe’s content, has long been the subject of debate among scientists. While some argue that it doesn’t exist, new observations from the James Webb Space Telescope (JWST) provide strong evidence for its presence.
The Bullet Cluster, a galaxy cluster located 3.8 billion light-years away, is one of the most studied objects in space. It consists of two clusters colliding and merging. Researchers have previously found that the distribution of hot gas in the cluster can be separated from dark matter using gravitational lensing. This method allows scientists to infer the distribution of mass within the cluster.
The JWST’s near-infrared instrument was used to measure thousands of galaxies, stars, and even objects kicked out of their galaxies, which allowed researchers to “weigh” the cluster with greater accuracy. The new observations confirmed previous findings, particularly when it came to intracluster stars, which can be used as a proxy for dark matter.
The study’s lead author, Sangjun Cha, said that confirming the reliability of intracluster light as a tracer of dark matter in a highly dynamic environment like the Bullet Cluster is a significant breakthrough. The observations suggest that the large cluster may have suffered minor collisions before and after merging with the other cluster.
These findings support the idea that dark matter plays a crucial role in the peculiarities of certain objects in space, such as the Bullet Cluster. While some scientists still argue for alternative explanations, the new evidence from JWST provides strong evidence for the existence of dark matter.
Source: https://www.iflscience.com/stunning-new-jwst-observations-give-further-evidence-that-dark-matter-is-a-real-substance-79834