Electrical currents in atmospheric lightning strokes generate impulsive radio waves in a broad range of frequencies, called atmospherics. These waves can be modified by their passage through the plasma environment of a planet into the form of dispersed whistlers1. In the Io plasma torus around Jupiter, Voyager 1 detected whistlers as several-seconds-long slowly falling tones at audible frequencies2. These measurements were the first evidence of lightning at Jupiter. Subsequently, Jovian lightning was observed by optical cameras on board several spacecraft in the form of localized flashes of light3,4,5,6,7. Here, we show measurements by the Waves instrument8 on board the Juno spacecraft9,10,11 that indicate observations of Jovian rapid whistlers: a form of dispersed atmospherics at extremely short timescales of several milliseconds to several tens of milliseconds. On the basis of these measurements, we report over 1,600 lightning detections, the largest set obtained to date. The data were acquired during close approaches to Jupiter between August 2016 and September 2017, at radial distances below 5 Jovian radii. We detected up to four lightning strokes per second, similar to rates in thunderstorms on Earth12 and six times the peak rates from the Voyager 1 observations13.
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We acknowledge all members of the Juno mission team, especially the engineers and staff of the Juno Waves instrument. The research at the University of Iowa was supported by NASA through contract 699041X with the Southwest Research Institute. The work of I.K. and O.S. was supported by the MSM100421701 and LTAUSA17070 grants and the Praemium Academiae award.
Supplementary Figures 1–10, Supplementary Tables 1–2, Supplementary Audio Guide
Sound of whistler from Fig. 1a
Sound of whistler from Fig. 1b
List of historical optical lightning detections on Jupiter
List of Jovian rapid whistlers observed by Juno