What is Jupiter’s Great Red Spot?

The bright and vibrant colors of the planet Jupiter already has become much colorful and striking to the eyes because of the existence of the Great Red Spot on its surface. However, this is not just a mere spot. The Great Red Spot is known as a high-pressure region or a storm located in the southern hemisphere of Jupiter. It has captured the eyes of many people for generations. What is it about the Great Red Spot that captivates humans for so long? Let us know more about Jupiter’s striking Great Red Spot, its origin, and its story. 


In 1831, amateur astronomer Samuel Heinrich Schwabe first noticed this big red spot on the surface of the planet Jupiter. Astronomers said, despite being discovered in 1831, the Great Red Spot might exist even before that. In 1665, astronomer Gian Domenico Cassin wrote something regarding a “Permanent Storm.” Some astronomers think that this storm he was talking about was the Great Red Spot. All they know is that Jupiter’s red spot has been there for at least 150 years already. 


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The Great Red Spot found circling in Jupiter’s southern hemisphere is a giant storm, two times bigger than the Earth. The winds in the center of the storm are relatively calm. However, wind speeds on the edges of the storm could reach 270-425 mph. This speed is over twice the speed Earth’s most intense hurricanes have, which can reach up to 175 mph. 

Astronomers discovered that the Great Red Spot moves in a counterclockwise direction with a period of almost six Earth days. It is equivalent to fourteen days in Jupiter. They also discovered that the Great Red Spot has a higher altitude than most of Jupiter’s clouds, which means that the spot is colder than any of these clouds. 

The storm contains two swirling bands. The first one is the eastward-moving atmospheric band, and the second one is the westward-moving band to its south. These bands are the reason why the giant red storm formulated. They are also the ones that keep the storm spinning for many centuries now. 

The telescopes here on Earth noticed that the Great Red Spot changes its color every year- it may be salmon-red the turns into gray. They believed this happens because the spot could blend into the colors of the cloud belts surrounding the planet Jupiter. Spacecrafts sent to observe Jupiter’s spot revealed that high-altitude white clouds could cover and dominate the pinking cloud belts of Jupiter. It causes the grey impression of the Great Red Spot that astronomers see from Earth. 

Astronomers still have not yet know the reason for the red coloration in Jupiter’s spot. They speculate that it is because of the sulfur and phosphorus compounds and organic materials on the planet. They believe that lightning discharge and high-altitude photochemical reactions on the surface of the planet Jupiter produced these materials and compounds. 

The Great Red Spot was about 30,000 miles or 48,000 kilometers in length when astronomers observed it in the 19th century. They also noticed that the spot is constantly shrinking. In 1979, the Great Red Spot measured by the Voyager spacecraft became 14,500 miles or 23,000 kilometers in length. In 2012, astronomers observed that the spot became more circular, and it is shrinking faster at almost 580 miles or 980 kilometers per year. 

The longevity of the Great Red Spot on Jupiter’s surface is no doubt because of its size, and it might also be because the planet does not have any solid surface- it is most likely fluid throughout its entire surface. The “sky” of the planet Jupiter can be measured 44 miles or 70 kilometers deep. It is made up of cloud layers which consist of ammonia ice, vapor, and water ice. The condensation of these particles in the lower levels of the atmosphere of Jupiter may have caused the gigantic storm. The hurricane may get its energy from smaller eddies (circular current of water) that merge with it or from the fast-moving currents from either side of the storm. 

The astronomers believe that beneath the layers of the planet Jupiter’s “sky,” there is an ocean of liquid hydrogen that exists. They also think that underneath that ocean is the core of the planet- however, they are still unsure of the components of the planet Jupiter. Storms on Earth start slowing down and eventually break apart as they reach solid ground. Since the surface of Jupiter is purely liquid, the Great Red Spot has nowhere to make landfall, causing the storm to continue raging on and on.