Astronomers discover repeating radio bursts from distant 'dead' galaxy

Astronomers have recently detected fast-repeating radio bursts (FRBs) emanating from an unexpected source: a distant "dead" galaxy that theoretically lacks the energy-producing young stars typically associated with such signals. These FRBs, which are brief flashes of radio waves lasting milliseconds, have generally been linked to young, magnetized neutron stars forming in energetic stellar environments. However, the galaxy from which these bursts, designated FRB 20240209A, is said to originate does not fit this profile, as it primarily contains old stars.

The researchers' expectations were rooted in the understanding that FRBs usually arise in regions with active star formation, as noted by Vishwangi Shah, a PhD student at McGill University. Contrarily, the ancient elliptical galaxy in question, located approximately 2 billion light-years from Earth, is known to harbor only older stellar remnants, raising intriguing questions about the origins of these bursts.

Using the Canadian Hydrogen Intensity Mapping Experiment (CHIME) telescope, Shah and her team detected multiple bursts from the same location but initially struggled to pinpoint the exact source. They subsequently employed the Gemini North telescope in Hawaii for more precise measurements, leading to the surprising realization that there was no other identifiable galaxy nearby.

This discovery stands out in the broader context of FRB research; thousands of radio bursts have been documented since their discovery in 2007, yet the sources of only about 100 have been definitively identified, all located in active star-forming regions. Shah emphasized that FRB 20240209A represents an anomaly that challenges existing theories about the mechanisms behind FRBs.

The current hypothesis suggests the bursts could be linked to two neutron star remnants that are either merging or collapsing. Continued examination of these radio bursts is expected to enhance our understanding of the cosmic environment between their origin and the Milky Way, offering valuable insights into distant regions of space and the fundamental workings of the universe.