Aside from being the largest planet in the solar system, Jupiter is also known because of its "Great Red Spot" which is the largest and longest lasting storm on the planet. It measures 13,000 kilometers in diameter and has been there for the last 400 years. Now, this unique feature of Jupiter is slowly disappearing. In 1880, astronomer and artist Ētienne Trouvelot sketched Jupiter and the Great Red Spot. The drawing shows how large it was. According to Glen Orton, a senior research scientist at NASA's Jet Propulsion Laboratory who studies Jupiter, way back in 1870's drawings and images of Jupiter's storm looked like a great red sausage. In fact, three piles of earth could fit inside. However, looking at it now, the storm is now as big as the earth.
"It's just been shrinking since then, "shared Orton, adding, "I've said someday it might become the Greatest Red Circle and some scientists think it's not going to be stable and it'll become the GRM: The Great Red Memory."
The formation of the propeller of the swirling red clouds of the storm had been spotted along its edge. "This is very uncharted territory," said Orton. "We've never seen it like this before."
The same observations were made in 2017 along the western edge of the storm but as what Orton said the circumstances were different. "What is unusual now, is there visibly dark line going around the planet for the first time."
With the help of amateur astronomers, they were able to determine things that are undetected, according to Orton. "The amateur community is the one resource that gets measurements of Jupiter," he explained. "They do continuous monitoring."
An image of some parts of Jupiter's Great Red Spot on May 27 was submitted by amateur astronomer Christopher Go from Cebu City, Philippines, according to CBC.
"The oval is...bleeding material from the GRS," said Go. "This material will rotate around the GRs counterclockwise. As it goes south to the GRS, it is expected to distort the GRS maybe causing it to shrink more."
"At any given moment, there is someone, somewhere around the world imaging Jupiter," he added. "This really helps us in our long term understanding of Jupiter."
As of now, NASA's Juno is still orbiting Jupiter and will sew over the GRS toward the end of July. Moreover, scientists are still not sure when the Great Red Spot break apart. As what Orton said, the great storm had shrunk at about 5 to 15%.
"I would have thought that one propeller would have come off and that would have been the end of it," Orton concluded. "But there was another storm that came by and another shard have come off so time will tell."