The familiar axisymmetric zones and belts that characterize Jupiter's weather system at lower latitudes give way to pervasive cyclonic activity at higher latitudes. Two-dimensional turbulence in combination with the Coriolis β-effect (that is, the large meridionally varying Coriolis force on the giant planets of the Solar System) produces alternating zonal flows. The zonal flows weaken with rising latitude so that a transition between equatorial jets and polar turbulence on Jupiter can occur. Simulations with shallow-water models of giant planets support this transition by producing both alternating flows near the equator and circumpolar cyclones near the poles. Jovian polar regions are not visible from Earth owing to Jupiter's low axial tilt, and were poorly characterized by previous missions because the trajectories of these missions did not venture far from Jupiter's equatorial plane. Here we report that visible and infrared images obtained from above each pole by the Juno spacecraft during its first five orbits reveal persistent polygonal patterns of large cyclones. In the north, eight circumpolar cyclones are observed about a single polar cyclone; in the south, one polar cyclone is encircled by five circumpolar cyclones. Cyclonic circulation is established via time-lapse imagery obtained over intervals ranging from 20 minutes to 4 hours. Although migration of cyclones towards the pole might be expected as a consequence of the Coriolis β-effect, by which cyclonic vortices naturally drift towards the rotational pole, the configuration of the cyclones is without precedent on other planets (including Saturn's polar hexagonal features). The manner in which the cyclones persist without merging and the process by which they evolve to their current configuration are unknown.

We have used high-resolution images obtained with JunoCam onboard the Juno spacecraft during its close flyby of Jupiter on 2017 July 11, to study the dynamics of the Great Red Spot (GRS) at the upper cloud level. We have measured the horizontal velocity and vorticity fields using the clouds as tracers of the flow. We have analyzed a variety of cloud morphologies that serve to characterize different underlying dynamic processes. Long undulating dark gray filaments (2000–10000 km) circulate around the outer part of the vortex moving at high speed (∼120–140 m s−1) where mesoscale waves (wavelength 75 km) indicate stable conditions in this region. At mid distance from the center, a large eddy (radius ∼500 km) is observed in a region of intense horizontal wind shear whereas on the opposite side, compact cloud clusters with cell sizes of ∼50 km, indicative of shallow convection, are observed. The core of the GRS (∼5000 × 3000 km2) is turbulent where the circulation has weakly cyclonic and anticyclonic regions. This variety of phenomena occurs in the upper ammonia cloud layer and haze (thickness ∼20–50 km) that represents the top of a dynamical system with a much deeper circulation.

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We describe a huge planetary‐scale disturbance in the highest‐speed Jovian jet at latitude 23.5°N that was first observed in October 2016 during the Juno perijove‐2 approach. An extraordinary outburst of four plumes was involved in the disturbance development. They were located in the range of planetographic latitudes from 22.2° to 23.0°N and moved faster than the jet peak with eastward velocities in the range 155 to 175 m s−1. In the wake of the plumes, a turbulent pattern of bright and dark spots (wave number 20–25) formed and progressed during October and November on both sides of the jet, moving with speeds in the range 100–125 m s−1 and leading to a new reddish and homogeneous belt when activity ceased in late November. Nonlinear numerical models reproduce the disturbance cloud patterns as a result of the interaction between local sources (the plumes) and the zonal eastward jet.

Jupiter's Great Red Spot (GRS) is the archetype and the best studied of all the vortices in the giant planets, but its origin and fate remain mysterious. The first detailed studies of this anticyclone started with the Voyager 1 and 2 flybys in 1979, when its velocity field, vorticity and temperature structure at the upper cloud level were measured (Conrath et al., 1981;Flasar et al., 1981;Mitchell et al., 1981). Over the past 130 years, the GRS has decreased in size by half (Rogers, 1995;Simon et al., 2018) and has undergone numerous interactions with a variety of different dynamical features (anticyclonic vortices and open circulating cells called South Tropical Disturbances, STrD) that develop at its latitude east and west of its location (Li et al., 2004;