Two neutron stars slammed together far away from Earth. The energy of their collision lit up their corner of the sky with a brief flash of gamma radiation, followed by a softer, longer-lasting glow across the electromagnetic spectrum. Peering into that fading light, researchers spotted an unusual infrared signal, possibly the first-ever recorded signature of a newborn cosmic behemoth, a magnetar.
A magnetar is a neutron star with an unusually strong magnetic field. Astronomers have spotted magnetars elsewhere in the universe, but they’ve never before seen one being born. Researchers suspect this because of an unusual pattern of flashing light. First there was a short, ultrabright burst of gamma radiation (GRB). Then there was a longer-lasting, glowing ‘kilonova’, a telltale sign of neutron stars colliding. And that glow was much brighter than usual, suggesting a phenomenon astronomers had never seen before.