As shown in the image above: Jupiter's "weather layer" of cloud formation gives the gas giant planet a streaked appearance. In this composite image, you can see the planet in infrared (left) and visible light (right). The image was taken by the Gemini North Telescope and NASA's Hubble Space Telescope, respectively.
On Jupiter, a storm has been brewing for more than 300 years. This swirling high-pressure region, known as the Great Red Spot, is clearly visible in space and spans an area of more than 16,000 kilometers wide in Jupiter's atmosphere and is about a quarter of Earth's diameter.
But this stirring storm is far more complicated than we see. According to two new studies published Oct. 28 in the journal Science, Jupiter's Great Red Spot is very deep, extending 480 kilometers into the planet's atmosphere, about 40 times deeper than The Mariana Trench on Earth.
That's much deeper than the researchers expected, and the storm's bottom is well below atmospheric levels, where water and ammonia are expected to condense into clouds. The researchers say the storm's deep roots suggest that some of the processes that are not yet known link Jupiter's interior and deep atmospheres make the scale of intense meteorological events much larger than previously thought.
Scott Bolton, principal investigator of NASA's Juno mission and lead author of one of the new papers, said: "We have for the first time truly understood how Jupiter's beautiful and violent atmosphere works. ”
Both new studies rely on observations from NASA's Juno probe. The Juno probe entered jupiter orbit in 2016 and has made 36 flights to date to the gas giant, which is nearly 140,000 kilometers in diameter. In one study, scientists examined the Great Red Spot using the detector's microwave radiometer, a tool for detecting microwaves emitted from the planet's interior. NASA said that unlike the radio and infrared radiation emitted by the gas giant, microwaves can penetrate the planet's thick clouds.
By studying the microwave radiation that allowed it to pass through the Great Red Spot, the authors of the first study determined that the storm was more than about 350 kilometers deep.
A second study found that the spot may be larger than before. The authors of the paper used Juno's gravity detection tool to detect the Great Red Spot. The researchers combined data from 12 flights through the site, including two direct overhead flights, to calculate where the storm gathered the most atmospheric mass on Earth, thereby estimating its depth. The researchers determined that the point reached a maximum depth of about 500 kilometers below the top of the cloud.
Despite its deep appearance, the researchers said, the Great Red Spot is still much shallower than the huge airflow that surrounds it and powers it. These wind bands extend to depths of about 3,200 km below the clouds. The reason for this discrepancy remains a mystery, but the relatively shallow black spots may be due to another phenomenon recently discovered: the Great Red Spot is shrinking. Since 1979, its width has been reduced by about a third.
The future of the site remains uncertain, but whatever happens, Juno will continue to keep an eye on our huge gas neighbor in space.