A Solar Wind Squeeze May Have Strengthened Jovian Aurorae

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By Sarah Stanley, Eos/AGU. 

Excerpt: Spectacular aurorae dance and shimmer nearly continuously at Jupiter’s poles. ...Sometimes, Jupiter’s aurorae grow much brighter for hours or days at a time. ...clarifying the solar wind’s role in any one brightening event would require taking simultaneous measurements of Jupiter’s magnetosphere and aurorae and their relationship with the solar wind—a difficult undertaking. ...NASA’s Juno mission has made such simultaneous measurements possible. Giles et al. used data... from two of Juno’s onboard instruments...as Juno neared Jupiter in its elliptical orbit on 6 December, the spacecraft was overtaken by the outer edge of the shrinking magnetosphere before later reentering it closer to Jupiter. ...Another of Juno’s instruments, its ultraviolet spectrograph, measured the aurora’s peak power at this time to be 12 terawatts—6 times its baseline power level. ...the researchers concluded that the powerful auroral display was likely triggered by the major solar wind shock compressing the magnetosphere. ...(Journal of Geophysical Research: Planets, https://doi.org/10.1029/2025JE009012, 2025)... 

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