Fig. 1: Juno-UVS observations of the northern auroral region of Jupiter during PJ22.

a Juno trajectory plotted in magnetic coordinates. The gray area indicates where the in situ measurements shown in Fig. 3 have been made. b False color UV map of the auroral structures observed onto Jupiter’s northern auroral region resulting from co-adding consecutive Juno-UVS data from 02:54:00 to 03:09:02. The colors represent various UV spectral bands: red, green, and blue tend to correspond to high-, medium-, and low-energy electron precipitation, respectively, while white indicates a mixture of energies^64,86.The magnetic footpaths of the Juno spacecraft and the Galilean moons are shown as orange and green lines, respectively. The auroral footpaths of Io, Europa, and Ganymede (green solid lines) were calculated using JRM33 + CON2020^36,87 while the Callisto footpath (green dashed line) was derived using JRM33 + KK2005⁷⁵ (see “UV maps” in Methods). The white triangles along the Juno footpath highlight Juno’s magnetic footprints with a 10 min time step. Juno’s magnetic footprints at the beginning and end of the Juno-UVS data integration time are represented by orange dots. The white boundaries show the statistical position of the main oval emissions. Orange crosses indicate the statistical location of the Main Alfvén Wing (MAW) spots of Io, Europa, and Ganymede⁴⁵. The footprints of the four Galilean moons are outlined by orange lines. The un-annotated Juno-UVS observation is displayed in Supplementary Fig. 3.