Mercury has a radiation belt, lasting days despite solar winds

Scientists have confirmed the existence of a dynamic electron radiation belt at Mercury, resolving a decades-long debate that began with initial observations from Mariner 10 in the 1970s. The newly discovered belt can persist for several Earth days under weak solar wind forcing. Researchers integrated data from the MESSENGER mission with new analysis techniques and simulations to reveal the structured belt and its variable morphology subject to solar wind activity. This establishes Mercury as a unique natural laboratory for studying radiation-belt physics in an extreme and rapidly changing environment. Mariner 10 first indicated the presence of energetic electrons surrounding Mercury in the 1970s, a finding that initiated a scientific discussion lasting over four decades before…