Episode 46: A crash of clusters

with Dr Kenda Knowles

In this episode, we are joined by Dr Kenda Knowles who is a Research Fellow at Rhodes University, South Africa. Kenda speaks with us about her work as an observational astronomer working on the MeerKAT.

Kenda has just released a beautiful new dataset called the MeerKAT Galaxy Cluster Legacy Survey (MGCLS). The Survey contains images of the radio emission from 115 clusters of galaxies!

The survey has detected very faint emissions from these clusters which can teach about how these clusters form and evolve and the gas and magnetic fields within them. They also contain a wealth of data still to be explored!

Here we see radio evidence of a powerful merger taking place between two or more massive groups of gas and galaxies. These structures (a so-called ‘halo’ near the center and two ‘relics’ surrounding it are seen in the galaxy cluster MCXC J0352.4-7401) trace the positions and strengths of cosmic magnetic fields and electron populations travelling near the speed of light. This MeerKAT image spans approximately 10 million light-years at the distance of the cluster, and is sprinkled with point-like radio emission from even more distant Milky Way-like galaxies. Adapted from K. Knowles et al., “The MeerKAT Galaxy Cluster Legacy Survey. I. Survey Overview and Highlights” (Astronomy & Astrophysics, in press). Image credit: SARAO.

 

Two giant radio galaxies (more than one million light-years from end to end) at the center of a large group of galaxies in the cluster Abell 194, revealing the presence of relatively narrow magnetic filaments in the region, as well as complex interactions between the radio emission from the two galaxies. The MeerKAT radio image is shown in orange, with an optical image dominated by normal galaxies shown in white. Adapted from K. Knowles et al., “The MeerKAT Galaxy Cluster Legacy Survey. I. Survey Overview and Highlights” (Astronomy & Astrophysics, in press). Image credit: SARAO, SDSS

 

 

This week’s guest

Episode Links

Kenda’s Twitter: https://twitter.com/kilokilok9

Rhodes Centre for Radio Astronomy Techniques & Technologies : https://ratt.center/

Knowles et al., “The MeerKAT Galaxy Cluster Legacy Survey. I. Survey Overview and Highlights“, accepted for publication in Astronomy & Astrophysics.

The MeerKAT telescope is operated by the South African Radio Astronomy Observatory, which is a facility of the National Research Foundation, an agency of the Department of Science and Innovation.