Juno spacecraft snaps stunning image of Jovian swirls

Jim Sharkey

During its most recent close flyby of Jupiter, NASA’s Juno spacecraft captured an image of clouds swirling in a Jovian jet stream. A brown oval known as a “brown barge” appears in the top-left portion of the image, in the North Temperate Belt region.

The image was taken at 5:58 p.m. PDT (8:58 p.m. EDT) on September 6, 2018 as Juno performed its 15th close flyby of Jupiter. The spacecraft was 7,600 miles (12,231 kilometers) above Jupiter’s cloud tops at the time the image was captured above a northern latitude of approximately 53 degrees.

Brown barges are cyclonic regions that are most often found within Jupiter’s dark Northern Equatorial Belt, although they are occasionally found in the planet’s Southern Equatorial Belt as well. Brown barges can be difficult to detect visually because their dark colors blends them in with their dark surroundings.

Occasionally, the dark material in the belt recedes, creating a lighter-colored background against which the brown barge is more visible. Brown barges usually dissipate after the entire cloud belt undergoes an upheaval and reorganizes itself.

The image was created by citizen scientists Brian Swift and Seán Doran using data from Juno’s JunoCam imager. The view has been rotated 90 degrees to the right from the original image. JunoCam raw images are available online for the public to peruse and process into image products.

In June of 2018, NASA approved extending Juno’s science operations until July 2021. This extension provides the $1 billion spacecraft with an additional 41 months in orbit around Jupiter and should enable the mission to achieve its primary scientific goals. Due to concerns about valves in the spacecraft’s fuel system, Juno is in a 53-day orbit rather than the initially planned 14-day orbit. The longer orbit means that collecting the required science data will take more time. The end of Juno’s primary mission is now scheduled for July 2021, with data analysis and mission close-out activities continuing into 2022.