Scientists say the Great Red Spot on Jupiter is moving unexpectedly

(CNN) – New observations of Jupiter’s Great Red Spot taken by the Hubble Space Telescope show that the 190-year-old storm moves like jelly and changes shape like a stress ball when squeezed.

The unexpected observations, which Hubble took over 90 days from December to March, show that the Great Red Spot is not as stable as it appears, according to astronomers.

The Great Red Spot (GRS) is an anticyclone, or large circulation of winds, in Jupiter’s atmosphere that orbits around a central area of ​​high pressure along the southern midlatitude cloud belt. The long-lasting storm is so large — the largest in the solar system — that Earth could fit inside it.

Although storms are generally considered unstable, the Great Red Spot has persisted for nearly two centuries. However, the changes observed in the storm appear to be related to its movement and size.

Time-lapse images show the vortex “vibrating” like jelly, expanding and contracting over time.

The researchers described the observation in an analysis published in Planetary Science Journal Shown on Wednesday 56th Annual Meeting of the Planetary Sciences Section of the American Astronomical Society (Boise, Idaho).

“While we knew that its motion varies slightly along its length, we did not expect to see the size fluctuate as well. As far as we know, the study’s lead author, Amy Simon, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, said in a statement. “He has not been identified before.”

“This is the first time we’ve gotten the shooting rhythm right from GRS,” Simon said. “With Hubble’s high resolution, we can say that the GRS is definitely compressing and expanding while moving faster and slower. “That was very unexpected.”

Astronomers have observed the famous crimson feature for at least 150 years, and sometimes observations lead to surprises, including the recent revelation that the storm’s oval shape can change dimensions and appear thinner or thicker at times.

Recently, a separate team of astronomers examined the core of the Great Red Spot using the James Webb Space Telescope to capture new details in infrared light. Hubble’s observations were made in visible and ultraviolet light.

The study was published on September 27 in Journal of Geophysical Research: Planets, It revealed that the Great Red Spot is cold in the center, causing ammonia and water to condense inside the vortex and form dense clouds. The research team also discovered phosphine within the storm, which could play “a role in generating those mysterious red colors” that make the Great Red Spot so distinctive, study co-author, a professor of planetary sciences at the University of California, Leicester in the UK, said in a statement.

NASA scientists use Hubble’s penetrating eye to track storm behavior once a year through the Outer Planet Atmospheres Legacy (OPAL) program, which Simon leads. Scientists use this software to observe the exoplanets in our solar system and see how they change over time.

But the new observations were taken separately by a program dedicated to studying the Great Red Spot in more detail, looking at how the storm changes over months, rather than in a single annual snapshot.

“To the untrained eye, Jupiter’s striped clouds and its famous red storm can appear stationary, stable and long-lasting for many years,” Fletcher said. “However, closer examination shows incredible variability, with chaotic climate patterns as complex as anything we have here on Earth. “Planetary scientists have struggled for years to see the patterns of this variation, anything that might give us insight into the physics behind this complex system.”

Fletcher was not involved in the new study.

Insights gained through the program’s observations of the largest storms in our solar system could help scientists understand what the climate might be like on exoplanets orbiting other stars. This knowledge can expand your understanding of weather processes beyond those we experience on Earth.

Simon’s team used high-resolution Hubble images to closely examine changes in the size, shape and color of the Great Red Spot.

“When we look closely, we see that a lot of things change from one day to the next,” Simon said.

The changes included the brightness of the storm’s core when the Great Red Spot is at its largest as it oscillates.

“As it accelerates and decelerates, the GRS is pressing against the stormy jet streams to its north and south,” study co-author Mike Wong, a planetary scientist at the University of California, Berkeley, said in a statement. “It’s similar to a sandwich where the slices of bread are forced to swell when there is too much filling in the middle.”

Dark spots on Neptune can move around the planet because there are no strong jet streams holding them in place, while the Great Red Spot is trapped between jet streams at southern latitude on Jupiter, Wong said.

Astronomers have observed the Great Red Spot shrinking since the OPAL program began a decade ago, and expect it will continue to do so until it reaches a stable, less elongated shape, which could reduce the oscillation.

“Right now, it overfills its latitude range relative to the wind field. Once it contracts in that range, the wind will hold it in place,” Simon said.

Fletcher said the new Hubble study completes more pieces of the puzzle about the Great Red Spot. He added that although scientists know that the storm’s westward drift has an unexplained 90-day oscillation, the pattern of acceleration and deceleration does not appear to change even though the storm is shrinking.

“By observing the GRS for a few months, Hubble showed that the anticyclone itself changes shape with this oscillation,” Fletcher said. “The change in shape is important, because it may affect how the edge of the vortex interacts with other passing storms. Combined with Hubble’s impressive images, this study shows the power of observing atmospheric systems over long periods of time.” You need this kind of monitoring to detect “about these patterns, and obviously the more you look, the more structure you see in the chaotic climate.”