Enlarge / The main body of NASA's Europa Clipper spacecraft is reflected in one of the mission's deployable solar array wings during testing at Kennedy Space Center in Florida. (credit: NASA/Frank Michaux) For a while earlier this summer, it looked like NASA's flagship mission to study Jupiter's icy moon Europa might miss its launch window this year. In May, engineers raised concerns that transistors installed throughout the spacecraft might be susceptible to damage from radiation, an omnipresent threat for any probe whipping its way around Jupiter.