An international team of astronomers has combined the power of 64 radio telescope dishes to detect the faint signatures of neutral hydrogen gas across cosmological scales. The South African-based MeerKAT telescope was instrumental in achieving this feat.
The Square Kilometre Array Observatory (SKAO), which has its headquarters at Jodrell Bank, Cheshire, is under construction. However, pathfinder telescopes are already in place, like the 64-dish array MeerKAT, to guide its design. Based in the Karoo Desert and operated by the South African Radio Astronomy Observatory (SARAO), MeerKAT will eventually become a part of the full SKAO.
MeerKAT and the SKAO will primarily operate as interferometers. As a result, astronomers will combine the array of dishes as one giant telescope capable of imaging distant objects with high resolution. “However, the interferometer will not be sensitive enough to the largest scales most interesting for cosmologists studying the Universe,” explained the co-lead author of the new research paper, Steven Cunnington. “Therefore, we use the array as a collection of 64 individual telescopes, which allows them to map the giant volumes of sky required for cosmology.”
A team at the University of the Western Cape has driven the single-dish mode of operation, having conducted several observations with MeerKAT. Furthermore, this ambitious project involves many other institutions spanning four continents. In the new research on arXiv, a team presents the first-ever cosmological detection using this single-dish technique. This team includes Steven Cunnington, Laura Wolz, and Keith Grainge,
The new detection is a shared clustering pattern between MeerKAT’s maps and galaxy positions determined by the optical Anglo-Australian Telescope. Since these galaxies trace the overall matter of the Universe, the strong statistical correlation between the radio maps and the galaxies shows the MeerKAT telescope is detecting large-scale cosmic structures. This is the first time astronomers will make such detection using a multi-dish array operating as individual telescopes. Because the full SKAO will rely on this technique, this marks a vital milestone in the roadmap for the cosmology science case with the SKAO.
Steven revealed that the team made the detection “with just a small amount of pilot survey data”. “It’s encouraging to imagine what will be achieved as MeerKAT continues to make increasingly larger observations, he concluded.
Faleti Joshua is an avid lover of space in all its incomprehensible nature. He holds both an LL.B and a B.L degree. Joshua is a lover of music and a lawyer in his free time.