A survey of small-scale waves and wave-like phenomena in Jupiter's atmosphere detected by JunoCam
Orton, Glenn et al. (2020), A survey of small-scale waves and wave-like phenomena in Jupiter's atmosphere detected by JunoCam, Dryad, Dataset, https://doi.org/10.5061/dryad.hdr7sqvdz
In the first 20 orbits of the Juno spacecraft around Jupiter, we have identified a variety of wave-like features in images made by its public-outreach camera, JunoCam. Because of Juno’s unprecedented and repeated proximity to Jupiter’s cloud tops during its close approaches, JunoCam has detected more wave structures than any previous surveys. Most of the waves appear in long wave packets, oriented east-west and populated by narrow wave crests. Spacing between crests were measured as small as ~30 km, shorter than any previously measured. Some waves are associated with atmospheric features, but others are not ostensibly associated with any visible cloud phenomena and thus may be generated by dynamical forcing below the visible cloud tops. Some waves also appear to be converging and others appear to be overlapping, possibly at different atmospheric levels. Another type of wave has a series of fronts that appear to be radiating outward from the center of a cyclone. Most of these waves appear within 5° of latitude from the equator, but we have detected waves covering planetocentric latitudes between 20°S and 45°N. The great majority of the waves appear in regions associated with prograde motions of the mean zonal flow. Juno was unable to measure the velocity of wave features to diagnose the wave types due to its close and rapid flybys. However, both by our own upper limits on wave motions and by analogy with previous measurements, we expect that the waves JunoCam detected near the equator are inertia-gravity waves.
These are measurements of physical properites of waves and wave-like features in Jupiter's atmosphere measured from cylindrical projections of JunoCam imaging in close approaches to Jupiter by the Juno spacecraft.
The measurments are limited to Jupiter orbits from 1 through 20, a period covering 2016 August 27 through 2019 May 29. They correspond to values plotted in Figures 16 and 17 of the main article, and Figures SI3-2 and SI3-3 of the Supplemental Information associated with this article. The table replicates the values shown in the Table of the Supplemental Information file.
The term ‘wavelength’ in column 8 refers to the distance between wave crests or discrete clouds. The tilt angle in column 9 is defined as 0º at the eastward direction of the wave packet to 180º in the westward direction of the wave packet. Thus, wave crests oriented more-or-less orthogonally to the direction of the wave packet, such as those shown in Figure 2 of the main article, have tilt angles close to 90º.
National Aeronautics and Space Administration, Award: Juno Mission Operations