On Aug. 20, Juice hurled into Earth’s magnetosphere, passing some 37,000 miles (60,000 km) above the Pacific Ocean, where the instruments got their first taste of the harsh environment that awaits at Jupiter. Racing through the magnetotail, JoEE and JENI encountered the dense, lower-energy plasma characteristic of this region before plunging into the heart of the radiation belts. There, the instruments measured the million-degree plasma encircling Earth to investigate the secrets of plasma heating that are known to fuel dramatic phenomena in planetary magnetospheres.