Jupiter’s radiation belts – and how to survive them

ESA’s Jupiter Icy Moons Explorer, Juice, is headed to the largest structure in the Solar System – not the gas giant itself but the mammoth magnetic field that it generates. Its exact size varies with the solar wind, but Jupiter’s magnetosphere is on average 20 million kilometres across, which is about 150 times wider than its parent planet and almost 15 times the diameter of the Sun. But within that field lurks a clear and present danger to space missions – intense belts of radiation much more energetic and intense than Earth’s own Van Allen belts.