A Stormy, Turbulent World: New Science Results From Juno Reveal 'Whole New Jupiter'

The first in-depth science results from the Juno mission at Jupiter were presented yesterday morning in a NASA media teleconference, and as referred to in the press release, they do indeed reveal “a whole new Jupiter.” The Solar System’s largest planet is incredibly active and complex, with polar cyclone storm systems as large as Earth, other storms which plunge deep down into the atmosphere and an immense, but lumpy, magnetic field. Juno has sent back the most detailed images ever taken of the planet, showing the atmospheric storms and other features, including Jupiter’s rings, as never before.
“We are excited to share these early discoveries, which help us better understand what makes Jupiter so fascinating,” said Diane Brown, Juno program executive at NASA Headquarters in Washington. “It was a long trip to get to Jupiter, but these first results already demonstrate it was well worth the journey.”

Scientists already knew of course, before Juno, that Jupiter was a dynamic planet, but as often happens in planetary science, it has turned out to be even more amazing than previously thought.
“We knew, going in, that Jupiter would throw us some curves,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “But now that we are here we are finding that Jupiter can throw the heat, as well as knuckleballs and sliders. There is so much going on here that we didn’t expect that we have had to take a step back and begin to rethink of this as a whole new Jupiter.”

The most obvious features are of course the planet’s belts of clouds with many circular storm systems, including the Great Red Spot. Even small telescopes can see some of these details. But now with Juno, we can see just how complex Jupiter’s atmosphere is, such as at the poles; previous spacecraft had glimpsed the poles before, but due to being in a polar orbit, Juno has provided the first detailed look at them, and they are incredible. While Jupiter’s equatorial regions are dominated by bands of clouds, the poles are covered in many cyclone-type storms each as large as the Earth. They are densely clustered and often rub against each other.
“We’re puzzled as to how they could be formed, how stable the configuration is, and why Jupiter’s north pole doesn’t look like the south pole,” said Bolton. “We’re questioning whether this is a dynamic system, and are we seeing just one stage, and over the next year, we’re going to watch it disappear, or is this a stable configuration and these storms are circulating around one another?”
Other data from Juno shows that the equatorial belts and zones are also perplexing – the belt closest to the equator penetrates very deep down into the atmosphere, while other belts apparently evolve into different structures farther down. These measurements come from Juno’s Microwave Radiometer (MWR), which samples the thermal microwave radiation from Jupiter’s atmosphere, from the top of the ammonia clouds to deep down in the atmosphere.

“We’ve known there’s a spike at the equator, but the new microwave data is showing that the spike goes way, way down into the abyss, 300 kilometers below the cloud,” said Leigh Fletcher of the University of Leicester, UK. “It suggests ammonia is being distributed by a weather system that penetrates much deeper than anyone expected.”

The whole inside of Jupiter is just working differently than our models expected,” said Bolton at the time.
Juno orbits Jupiter every 53 days, soaring over the planet’s poles, allowing the spacecraft to get views never possible before.
“Every 53 days, we go screaming by Jupiter, get doused by a fire hose of Jovian science, and there is always something new,” said Bolton. “On our next flyby on July 11, we will fly directly over one of the most iconic features in the entire solar system – one that every school kid knows – Jupiter’s Great Red Spot. If anybody is going to get to the bottom of what is going on below those mammoth swirling crimson cloud tops, it’s Juno and her cloud-piercing science instruments.”

One of the new images also shows Jupiter’s main ring, from the inside looking out, something not possible before. It is reminiscent of Cassini’s latest views of Saturn’s rings from between the planet and the rings. It’s been known for a long time that Jupiter has rings, they just are not nearly as prominent as Saturn’s.