Using data from the MeerKAT radio telescope, an international team of astronomers from the MeerKAT Absorption Line Survey (MALS) collaboration have compiled the largest catalog of radio sources from any MeerKAT survey to date. With this catalog, they were able to make a measurement of the cosmic radio dipole, a cosmological effect that arises from the Earth’s motion through the Universe, and provides an important test of our theories of cosmology at the largest scales. This new measurement demonstrates the value of the sensitive MeerKAT data, and shows that such deep data provide extremely valuable insights into the origin of the cosmic dipole effect.
The results are published in Astronomy & Astrophysics: The MeerKAT Absorption Line Survey Data Release 2: Wideband continuum catalogues and a measurement of the cosmic radio dipole (DOI).
Read more here.
Image: © MALS Team; A map of the sky overlaid on a portion of single MeerKAT pointings containing a few thousand radio sources. In the sky map, circles mark positions of 391 pointings containing a total of 971,980 sources. The arrow shows the direction of the cosmic dipole originally established by measurements of the cosmic microwave background radiation. The dipole effect will make the sources appear more numerous (red portion) in the direction of the motion and less numerous in the opposite direction (blue portion).