NASA’s Juno spacecraft data, combined with historical observations, indicates the absence of a shallow global magma ocean beneath Io’s surface. The findings, published in Nature on December 12, 2024, reshape scientific understanding of the solar system’s most volcanically active body. Juno, which arrived at Jupiter in 2016 and has completed over 60 orbits, conducted close flybys of Io in December 2023 and February 2024, approaching within 930 miles (1,500 kilometers) of the moon’s surface. The moon’s volcanic activity stems from tidal deformations caused by Jupiter’s gravitational pull during Io’s elliptical orbit, which varies by 2,175 miles (3,500 kilometers). “Whether there … Continue reading Jupiter’s Io Lacks Magma Ocean but Hosts 400 Volcanoes—NASA Juno Challenges Decades-Old Theories