ESA’s satellite INTEGRAL detected a burst of gamma-rays coming from the nearby galaxy M82. Follow-up observations by ESA’s XMM-Newton X-ray telescope did not find an afterglow from the explosion, leading researchers to conclude that the burst was an extra-galactic flare from a magnetar, a type of young neutron star with a strong magnetic field. The discovery, published in Nature, sheds light on the nature of these rare astronomical objects.
INTEGRAL’s IBAS software quickly identified the burst coming from the galaxy M82, located 12 million light-years away. The alert system was developed and operated by scientists and engineers from the University of Geneva (UNIGE) in collaboration with international colleagues. The detection of the burst from a nearby galaxy was deemed significant, prompting follow-up observations to confirm its origin and nature.
Although XMM-Newton’s observations did not reveal any afterglow in X-rays or visible light, researchers believe the burst was from a magnetar due to the lack of corresponding gravitational waves detected by Earth-based detectors. Magnetars are young neutron stars with exceptionally strong magnetic fields, capable of emitting energy in flares. This particular event marks the first confirmed detection of a magnetar flare outside of our galaxy.
The discovery of a magnetar in the star-forming region of M82 suggests that these objects are likely young neutron stars formed from massive stars that have ended their lives. Further research into magnetars in other extra-galactic star-forming regions will help astronomers understand the frequency of these flares and how neutron stars lose energy in the process. The search for more magnetars will continue to advance our knowledge of these extraordinary astronomical objects.
INTEGRAL’s wide field of view played a crucial role in capturing the short-duration burst of gamma-rays serendipitously. The satellite’s automatic data processing system allowed for immediate alerts to the astronomical community, enabling follow-up observations to be made quickly. The flexibility of INTEGRAL and XMM-Newton’s schedules proved essential in confirming the nature of the burst as a magnetar flare. This discovery highlights the importance of timely observations in studying rare astronomical phenomena.
The detection of an extra-galactic magnetar flare by ESA’s INTEGRAL satellite opens up new possibilities for understanding the nature and behavior of these rare astronomical objects. Further research into magnetars in star-forming regions of other galaxies will provide valuable insights into their formation, frequency of flares, and energy loss mechanisms. The collaboration between international researchers, including those from the University of Geneva, has contributed to this significant discovery, published in the prestigious journal Nature.
