Astronomers using South Africa's MeerKAT radio telescope have discovered the most distant hydroxyl megamaser ever observed, located approximately 5 billion light-years from Earth. The discovery, led by Dr. Marcin Glowacki of the International Centre for Radio Astronomy Research (ICRAR), was made as part of the Looking at the Distant Universe with the MeerKAT Array (LADUMA) survey. The megamaser has been named 'Nkalakatha', an isiZulu word meaning 'big boss'.
A megamaser is an intensely bright, naturally occurring cosmic laser, where the stimulated emission of microwave radiation is amplified. This particular signal is an 'OH megamaser', meaning it originates from hydroxyl molecules (made of one hydrogen and one oxygen atom) within galaxies undergoing intense star formation or from regions around supermassive black holes. The detection provides a unique tool for studying distant galactic collisions and mergers.
The signal was detected in a single night of observation, highlighting MeerKAT's sensitivity. Follow-up observations confirmed its distance and nature. Researchers believe the megamaser's power is likely fueled by a major collision between two galaxies, which triggers the massive star formation needed to produce such a strong and coherent signal.
This record-breaking discovery, published in *The Astrophysical Journal Letters*, allows astronomers to probe the conditions of the universe when it was much younger. The LADUMA survey continues, with the potential to find more of these rare cosmic phenomena and further our understanding of galaxy evolution.
