MeerKAT telescope detects ancient cosmic hydrogen signals

An international team of astronomers has successfully detected faint radio signals from neutral hydrogen gas dating back four to five billion years. Using South Africa’s MeerKAT radio telescope, researchers utilized a technique known as hydrogen intensity mapping to observe these emissions.

This method measures the collective radio emission of many unresolved galaxies simultaneously, offering a more efficient way to survey large-scale cosmic structures compared to traditional methods that combine radio data with optical galaxy surveys. The detected signals, specifically the 21-cm line, correspond to distances of approximately 3.67 and 4.76 billion light-years, representing an era when the universe was between 9 and 10 billion years old.

The study, published in The Astrophysical Journal Letters, relied on approximately 96 hours of archival data collected in 2018. The research involved a collaboration between the University of the Western Cape, the University of Manchester, the University of Edinburgh, McGill University, and the South African Radio Astronomy Observatory (SARAO).