Using observational data from the MeerKAT radio telescope in South Africa, an international team of astronomers made the most detailed images of the largest cosmic shock waves ever observed.
Galaxies gathered in so-called galaxy clusters are held together by gravity. Sometimes this gravity attracts galaxy clusters towards each other, leading to the collision, the largest astronomical event since the universe’s formation.
The collision of galaxy clusters creates gigantic cosmic shock waves. These cosmic shock waves travel through the newly formed galaxy cluster.
Recently, astronomers led by Dr. Francesco de Gasperin, a former Junior professor at Universität Hamburg, have successfully created images of the largest shock wave ever observed. The high-resolution images from the galaxy cluster Abell 366 offer unique insights into the structure of cosmic shock waves.
Francesco de Gasperin explains, “Cosmic shock waves are full of surprises and much more complex than we initially thought. The shock waves act as giant particle accelerators and accelerate electrons almost to the speed of light. When these fast electrons cross a magnetic field, they emit long-wave radiation that can be observed with the help of radio telescopes. The shock waves are threaded by an intricate pattern of bright filaments that trace the location of giant magnetic field lines and the regions where electrons are accelerated.”
“Abell 3667 was formed a billion years ago, but what we are measuring today took place about 800 million years ago. At that time, the shock waves propagated at 1500 kilometers per second and were about 60 times the size of our Milky Way.”
- F. de Gasperin et al., MeerKAT view of the diffuse radio sources in Abell 3667 and their interactions with the thermal plasma, Astronomy & Astrophysics (2022). DOI: 10.1051/0004-6361/202142658