Science.-Hubble observes that the external wind of the Great Red Spot accelerates

MADRID, 28 (EUROPA PRESS)

The Hubble Space Telescope has observed that the winds in the outermost “lane” of Jupiter’s Great Red Spot are accelerating.

Researchers analyzing Hubble’s regular “storm reports” for more than a decade found that the average wind speed just within the limits of the storm, known as the high-speed ring, has increased by as much as 8 percent. between 2009 and 2020. In contrast, winds near the innermost red region are moving significantly slower.

The crimson clouds from the massive storm are spinning counterclockwise at speeds in excess of 600 kilometers per hour, and the vortex is larger than Earth itself. The red spot is legendary in part because humans have observed it for more than 150 years.

“When I initially saw the results, I asked ‘Does this make sense?’ No one has seen this before, “Michael Wong of the University of California, Berkeley, who led the analysis, said in a statement.” But this is something only Hubble can do. Hubble’s longevity and ongoing observations make this possible. revelation”.

We use satellites and planes in Earth orbit to track large storms on Earth closely in real time. “Since we don’t have a storm chaser plane on Jupiter, we can’t continuously measure winds at the site,” explained Amy Simon of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who contributed to the research. “Hubble is the only telescope that has the kind of temporal coverage and spatial resolution that can capture Jupiter’s winds in this detail.”

The change in wind speed that they have measured with Hubble amounts to less than 2.5 kilometers per hour per Earth year. “We’re talking about such a small change that if you didn’t have eleven years of Hubble data, we wouldn’t know what happened,” Simon said. “With Hubble we have the precision we need to detect a trend.” Hubble’s ongoing monitoring allows researchers to review and analyze their data very precisely as they continue to aggregate. The smallest features Hubble can reveal in the storm are just 150 kilometers across.

“We found that the average wind speed in the Great Red Spot has increased slightly over the last decade,” added Wong. “We have an example where our analysis of the two-dimensional wind map found abrupt changes in 2017 when there was a large convective storm nearby.”

To better analyze the abundance of Hubble data, Wong took a new approach to his data analysis. It used software to track tens to hundreds of thousands of wind vectors (directions and speeds) each time Hubble looked at Jupiter. “It gave me a much more consistent set of speed measurements,” Wong explained. “I also ran a battery of statistical tests to confirm whether it was justified to call this an increase in wind speed. It is.”

What does the speed increase mean? “That’s difficult to diagnose, since Hubble can’t see the bottom of the storm very well. Anything below the cloud tops is invisible in the data,” Wong explained. “But it’s an interesting piece of information that can help us understand what fuels the Great Red Spot and how it maintains energy.” There is still a lot of work to do to fully understand it.

Astronomers have conducted ongoing studies of the solar system’s “king” of storms since the 1870s. The Great Red Spot is an outcrop of material from the interior of Jupiter. Viewed from the side, the storm would have a tiered wedding cake structure with tall clouds in the center cascading down to its outer layers. Astronomers have noticed that it is shrinking in size and becoming more circular than oval in observations spanning more than a century. The current diameter is 15,000 kilometers wide, which means that the Earth could still fit inside it.