A big brown storm rages on Jupiter

On its 15th flight over Jupiter, NASA's Juno spacecraft captured a rare image of a Jovian "brown barge". It is not as impressive or picturesque as the Great Red Spot on the largest planet in our solar system.

According to NASA, brown barges are also large cyclonic regions that typically form in the dark northern equatorial belt of Jupiter or, less frequently, in the dark southern equatorial belt. This particular storm is located in the southern belt.

Juno, in orbit around Jupiter since July 2016, took this photo on September 6, 2018 at a distance of 11,950 km from the summits of the planet. The enhanced color image was created by citizen-researcher Kevin M. Gill, who used data from the JunoCam of the spacecraft, which is publicly available. NASA says this is the first close-up of this atmospheric phenomenon, providing unprecedented insight into the detailed structures of the storm.

Brown ovals are usually hard to see, but this time we were lucky. As NASA describes in a press release, "They can often be difficult to detect visually because their color blends into dark environments. At other times, as with this image, the material of the dark belt recedes, creating a lighter background against which the brown barge is more visible.

This atmospheric feature is reminiscent of Jupiter's Great Red Spot – an anticyclonic storm that has been continuously observed by astronomers over the past 350 years. Unlike the persistent red patch, brown barges do not last very long. This storm will eventually dissipate and will likely go through a new reorganization cycle. Most elements of the belt and Jupiter's areas are short-lived and can last from three to fifteen years.

Juno has now completed 15 overflights of the gas giant. His next meeting will be on October 29, 2018. The good news is that Juno is still halfway through his mission; The spacecraft is expected to make 20 more flyovers, the last one taking place on July 30, 2021. Hopefully, there will be many more brown spots and other exotic phenomena in the months and years to come.