NASA’s Voyager 1 views Jupiter’s Great Red Spot. Credit: NASA’s Goddard Space Flight Center.
The massive storm near the gas giant’s equator has shrunk, but collisions with a series of anticyclones are likely only deep.
The stormy, centuries-old maelstrom of Jupiter‘s Big Red Spot was shaken but not destroyed by a series of anticyclones that crashed into it over the past few years.
The smaller storms cause pieces of red clouds to flake off, causing the larger storm to shrink in the process. But the new study found that these interruptions are ‘superficial’. They are visible to us, but they are only skin deep on the Red Spot, and do not affect its full depth.
The new study is in the Journal of Geophysical Research: Planets, AGU’s journal for research on the formation and evolution of the planets, moons and objects of our solar system and beyond.
‘The intense root of the [Great Red Spot]Agustín Sánchez-Lavega, a professor of applied physics at the University of the Basque Country in Bilbao, Spain, and lead author of the new article, along with its greater size and depth compared to the interacting alternating trees. As the larger storm absorbs these smaller storms, it “acquires energy at the expense of their rotational energy.”
A flake of red peel from Jupiter’s Big Red Spot during an encounter with a smaller anticyclone, as seen by the Juno spacecraft’s high-resolution JunoCam on February 12, 2019. Although the collisions appear violent, planetary scientists believe they mostly have surface effects. is, like the crust on a crème brûlée. Credit: AGU / Journal of Geophysical Research: Planets
The Red Spot has shrunk for at least the past 150 years and dropped from a length of about 40,000 kilometers (18750 miles) in 1879 to about 15,000 kilometers (9,320 miles) today, and researchers are still unsure about the causes of declining, or indeed how the spot was formed in the first place. The new findings show that small anticyclones may help maintain the Big Red Spot.
Timothy Dowling, a professor of physics and astronomy at the University of Louisville, who is a planetary atmospheric dynamics expert not involved in the new study, said it was an exciting time for the Red Spot. ‘
Stormy collisions
Prior to 2019, the larger storm hit only a few anticyclones a year, while it was recently hit by as many as two dozen a year. ‘It’s really being launched. It sounded very alarming, “said Dowling.
Sánchez-Lavega and his colleagues were curious to see if these relatively smaller storms disrupted their big brother’s turn.
The iconic feature of the gas giant is close to its equator and earthly concepts of a major bad storm have been disappearing for at least 150 years since the first confirmed observation, although observations in 1665 were possibly from the same storm. The Great Red Spot is about twice the diameter of the Earth and blows at a speed of up to 540 kilometers per hour along its periphery.
“The [Great Red Spot] is the archetype among the vortices in planetary atmosphere, ”said Sánchez-Lavega, adding that the storm is one of his” favorite features in planetary atmosphere. “
Cyclones such as hurricanes or typhoons usually revolve around a center of low atmospheric pressure and turn counterclockwise in the northern hemisphere and clockwise in the south, either on Jupiter or on Earth. Anticyclones rotate in the opposite way as cyclones, around a center with high atmospheric pressure. The Great Red Spot is itself an anticyclone, although it is six to seven times as large as the smaller anticyclones that collide with it. But even these smaller storms on Jupiter are about half the size of the earth and about ten times the size of the largest hurricanes on earth.
Sánchez-Lavega and his colleagues have been watching satellite images of the Great Red Spot for the past three years Hubble Space Telescope, the Juno spacecraft in orbit around Jupiter and other photographs taken by a network of amateur astronomers using telescopes.
Devoured by storms
The team found that the smaller anticyclones move through the high-speed edge of the Big Red Spot before circling the red oval. The smaller storms create chaos in an already dynamic situation, temporarily changing the Red Spot’s 90-day oscillation and ‘tearing the red clouds from the main oval and forming streamers’, Sánchez-Lavega said.
“This group did an extremely careful, very thorough job,” Dowling said, adding that the peeling of red material we see is similar to a crème brûlée effect, with a vortex extending a few miles up the surface occurs which does not have much impact on the 200 km depth of the Great Red Spot.
The researchers do not yet know what caused the red spot to shrink over the decades. But these anticyclones can sustain the giant storm for the time being.
‘The intake of [anticyclones] is not necessarily destructive; it can increase the GRS rotation speed, and perhaps maintain it in a stable state over a longer period of time, ”said Sánchez-Lavega.
Reference: “Jupiter’s Great Red Spot: Strong Interactions with Incoming Anticyclones in 2019” by A. Sánchez-Lavega, A. Anguiano-Arteaga, P. Iñurrigarro, E. Garcia-Melendo, J. Legarreta, R. Hueso, JF Sanz- Requena, S. Pérez-Hoyos, I. Mendikoa, M. Soria, JF Rojas, M. Andrés-Carcasona, A. Prat-Gasull, I. Ordoñez-Extebarria, JH Rogers, C. Foster, S. Mizumoto, A. Casely, CJ Hansen, GS Orton, T. Momary and G. Eichstädt, March 17, 2021,.
DOI: 10.1029 / 2020JE006686