NASA’s Juno spacecraft reveals the massive structure of the iconic Great Red Spot of Jupiter, a gargantuan storm that has raged over the gas giant for centuries. Passing over the circular storm several times, Juno helped scientists confirm that the location not only exists on the upper surface, but stretches hundreds of miles around the planet itself.
We have known for a long time how Great the Great Red Spot is. The diameter of the storm is approximately 10,000 miles, or over 16,000 kilometers wide, which means that our planet Earth could fit completely inside the savage storm. But scientists never fully understood how deep the Great Red Spot was. Was it just a surface level event, or did it reach the depths of Jupiter?
Now, thanks to two science instruments on Juno, planetary researchers have discovered a fairly solid range for the location. They put the depth of the storm between 300 and 500 kilometers, or between 186 and 310 miles, according to a study published in Science. It might seem small compared to the width of the big red spot, but the depth still makes it a very dreadful weather event. “It means it’s a massive storm,” said Yohai Kaspi, Juno co-investigator at the Weizmann Institute of Science in Israel. The edge. “If you put this storm on Earth, it would spread all the way to the space station. So he’s just a monster.
Until this decade, our best way to study anything about Jupiter was to look at it from afar. Scientists could use NASA’s Earth-orbiting Hubble Space Telescope or other ground-based telescopes to study the Great Red Spot. These instruments helped determine the width of the storm, but scientists could only speculate on the overall structure of the place. “Some of them assumed it was going to be very, very shallow, like we were talking about tens of kilometers,” said Marzia Parisi, a researcher with the Juno science team at NASA’s Jet Propulsion Laboratory. The edge. “And others, they thought, ‘Well, in theory it could go right down to the heart of Jupiter.'”
Then, in 2011, NASA launched its Juno spacecraft, a probe designed to come closer to Jupiter than any other spacecraft before. Juno spent five years traveling in deep space, and in 2016 the vehicle entered a very large orbit around Jupiter, an orbit that would bring Juno close to the planet every 53 days. During these close passes, or “perijoves,” Juno collected the majority of its data on Jupiter and what might linger inside the gas giant.
Perhaps the most exciting part of Juno’s mission is that the spacecraft was the first to pass over the poles of Jupiter – areas of the planet that had never been seen before the mission began. . But in 2019, Juno made a little redirect. Scientists reoriented the spacecraft to pass over the Great Red Spot twice to better understand what is happening under the storm.
During these passes, Juno measured the location’s gravitational field in an attempt to determine the depth of the storm. The Great Red Spot is so large that the Juno spacecraft can actually feel the small disturbances in gravity produced by the storm. Ultimately, the gravity signal revealed that the storm did not extend more than 500 kilometers deep. The scientists then combined this information with previous microwave measurements taken by Juno in 2017, which revealed the storm was spreading to less up to 300 kilometers deep. These measurements set a fairly good maximum and minimum limit to the depth of the storm.
These are by far the best measurements we have of the structure of the Great Red Spot. But they also raise questions. On the one hand, the storm is deep, but not as deep as some of the surrounding jet streams, which extend as far as 1,800 miles, or 3,000 kilometers, across the planet. Juno also helped identify these metrics, and scientists aren’t sure why there is a gap there. “It’s surprising that it goes so deep … but it’s also surprising that it doesn’t go as deep as the jets,” says Parisi. “So there is something going on 500 kilometers away that essentially alleviates the Great Red Spot.”
This means that there is still a lot to learn about how things turn inside Jupiter. But thanks to Juno, scientists have a much more complete picture of the planet and its most famous storm than ever before. “Before, we only had this 2D view, just looking from the outside,” Kaspi explains. “And now we have a full three-dimensional view. “