NASA's Mars Odyssey spacecraft detected a powerful burst of X-rays and gamma rays on 15 April last year. Within 7 minutes, the burst reached the Wind satellite 1.5 million kilometres away from Earth, and reached Earth after 4.5 seconds. Several high-energy detection instruments including the Fermi Gamma-ray Space Telescope were triggered at almost the same time.

Since many instruments had detected this high-energy burst event, scientists could tell after studying that, the burst came from a spiral galaxy about 11 million light-years away, which can be considered as a close distance in the scale of the universe. Hence, It is believed that this burst was originated from a magnetar, rather than a usual gamma-ray burst. Otherwise, the signals will be much stronger than what have been detected.

Neutron stars are formed where some massive stars collapsed after the supernova explosion. Magnetar is a kind of neutron star with strong magnetic fields that is about 1,000 times stronger than an ordinary neutron star. Magnetars produce powerful flares that trigger gamma rays. This discovery helps astronomers to analyse the characteristics of the gamma rays from a magnetar, so as to distinguish the sources of different gamma-ray bursts in the universe.

More information: https://youtu.be/yXYvhYXBeP0

Credit: NASA's Goddard Space Flight Center