Astronomers observed a series of repeating gamma-ray bursts (GRBs) in July, an unprecedented phenomenon in 50 years of GRB studies.

Typically caused by the explosive death of a star or its destruction by a black hole, GRBs usually last milliseconds to minutes, but this event repeated three times over 24 hours, making it 100 to 1,000 times longer than typical bursts.

The exact cause remains unknown, though researchers have several working theories.

Scientists say understanding these bursts could provide new insights into the most extreme ways stars die, CNN has reported.

The discovery raises questions about whether this event is exceptionally rare or the first of many yet to be detected.