Jupiter’s Great Red Spot is a storm that has been raging for hundreds of years. It was first observed by Gian Domenico Cassini in 1665 and has been observed continuously since then, except for the period between 1713 and 1830. Even if storm Cassini wasn’t the storm we see today, the current red dot has been around for almost two centuries. While Saturn and other gas planets experience occasional major storms, they are not as persistent as Jupiter’s great storm. At least we thought so.

Jupiter’s blob stands out for its deep red color that stands out against the planet’s pale color in visible light. We still don’t know the origin of its color, but we do know that the storm pulled molecules from deep in Jupiter’s atmosphere. Ultraviolet light interacting with these molecules can form reddish-brown tholins, as we see in Titan’s atmosphere. We wouldn’t have discovered the red dot until modern times if it weren’t for its high-contrast appearance.

Saturn also experiences great storms from time to time. The most recent appearance occurred during the Cassini-Huygens mission, when a white dot pierced Saturn’s atmosphere and was dubbed the Great White Spot. A similar location was observed by the Hubble Space Telescope in 1994. Observations of white storms on Saturn were recorded as early as 1876. They were thought to be separate storms because they were observed at different latitudes. Storms occur every 20 to 30 years, and each storm only lasts a few years. However, a new study published Science Advances, This shows that storms last much longer.

Instead of observing Saturn in the visible spectrum, the team looked at radio data from the Very Large Array. Saturn’s upper atmosphere is largely transparent to radio waves, allowing astronomers to see much deeper into Saturn’s atmosphere. The team found disturbances in the deep layers of Saturn’s atmosphere, particularly due to the abundance of ammonia, a key component of the Great White Spots. These faults occur at latitudes associated with the occurrence of past storms. This means that Saturn’s periodic major storms have plagued the planet’s atmosphere for decades. The team even found a band of disruption that didn’t match the known observations, possibly from a storm that preceded the 1876 storm. It seems that remnants of Saturn’s storms can last for centuries.

Further observations may provide clues as to how these storms originate from Saturn. The next big storm may appear in a few years, and with the help of radio astronomy we will be able to observe how the deep layers of Saturn are creating storms on the planet’s surface. Source