Champaign, Illinois – Researchers are increasingly turning their attention to the phenomenon of kilonova events, celestial explosions caused by the collision of neutron stars. These events, which release bursts of matter, light, and subatomic particles, have raised concerns among some scientists about the potential risks they pose to life on inhabited planets, including Earth. While astronomers have extensively studied other cosmic hazards like supernova and active galactic cores, kilonova incidents remain less common and less understood.
Dr. Haille M. L. Perkins from the University of Illinois warns that any source emitting powerful ionizing radiation could have detrimental effects on Earth-like biospheres under certain circumstances. Neutron stars are the remnants of massive stars that have exploded in supernovae, leaving behind city-sized objects that are incredibly dense. Despite being small, neutron stars are powerful and can spin rapidly, emitting radiation beams and possessing strong magnetic fields.
Kilonovas are associated with the collision of two neutron star remnants, emitting gamma-ray and X-ray radiation that has the potential to strip away atmospheric layers on planets. This ionizing radiation can damage the ozone layer, leading to harmful solar ultraviolet rays reaching the surface. The energy released during kilonova events can exceed a threshold that weakens the atmosphere’s ability to block solar ultraviolet rays, posing a significant threat to Earth-like planets if located nearby.
Short gamma-ray bursts from neutron star collisions can result in off-axis viewers detecting measurable radiation, with the brightness depending on the interaction of the explosion with surrounding gas. Cosmic rays produced after the collision can penetrate atmospheres, form reactive molecules, and cause genetic mutations in cells. While kilonova collisions are rare, the potential impact on planets within the danger zone is significant, suggesting a lower risk compared to cosmic rays from supernovae.
Furthermore, the release of high-energy photons from kilonovas can lead to atmospheric ionization cascades, potentially triggering strong electrical currents that may impact power grids and cause satellite outages. The biological hazards of elevated radiation at the surface, threatening livestock, crops, and water sources, highlight the potential dangers kilonova events pose to technology. The study of kilonova activity is ongoing, with researchers hoping to gain further insights from future detections to better understand the risks associated with these rare celestial events.