“It is incredible that one narrow magnetic hot spot, the Great Blue Spot, could be responsible for almost all of Jupiter’s variation, but the numbers bear it out,” said Harvard’s Kimee Moore about the first definitive detection beyond our world by NASA’s Juno mission of an internal magnetic field that changes over time, a phenomenon called secular variation.
Radio signals from two NASA probes, Cassini at Saturn (above) and Juno at Jupiter, is allowing researchers to pierce the swirling clouds that hide the deep interiors of Jupiter and Saturn, where crushing pressure transforms matter into states unknown on Earth –“the two planets are more complex than we thought,” says Ravit Helled, a planetary scientist at the University of Zurich in Switzerland. “Giant planets are not simple balls of hydrogen and helium.”