A magnetar giant flare in the nearby starburst galaxy M82.

Magnetar giant flares are rare explosive events releasing up to 10 erg in gamma rays in less than 1 second from young neutron stars with magnetic fields up to 10 G (refs. ). Only three such flares have been seen from magnetars in our Galaxy and in the Large Magellanic Cloud in roughly 50 years.

Two giant outbursts of V0332+53 observed with INTEGRAL.

Context: In July 2015, the high-mass X-ray binary V0332+53 underwent a giant outburst, a decade after the previous one. V0332+53 hosts a strongly magnetized neutron star. During the 2004-2005 outburst, an anti-correlation between the centroid energy of its fundamental cyclotron resonance scattering features (CRSFs) and the X-ray luminosity was observed.