Astrophysicists have just proposed a new theory to explain the unique lensing phenomenon of the galaxy cluster Abell 3827, located about 1.3 billion light years from Earth. The research results are published in the journal Monthly Notices of the Royal Astronomical Society (MNRAS). Previous observations showed that the visible part of the cluster makes up only 10% of its mass, with the rest made up of dark matter. Additionally, due to the nature and arrangement of the galaxies in the cluster, it acts as an unusually strong gravitational lens. As a result, the light from the background objects, distorted by gravity, forms a bright blue ring at the edge of the cluster.

The ring is essentially a multiplied image of the same background object, but astronomers don’t know exactly how many images are created through the lens. In the new paper, scientists suggest that the lens observed in the cluster is due to its three-dimensional characteristics. Previous theories described lenses as thin and flat. According to the new theory, Abell 3827’s gravitational lens is shaped like a wafer, with different parts having different thicknesses – a feature that could explain why the cluster appears more stretched in the sky. some parts compared to others. In this case, the galaxies forming a cluster should not be at the same distance from Earth.

source: https://academic.oup.com/mnras/article-abstract/526/2/2776/7295481?redirectedFrom=fulltext&login=false