When you spend more than $1 billion on a spacecraft, it can be a nervous wait to see if everything pays off. But if and when it does, the results can be rather glorious. And NASA’s Juno spacecraft has just paid off in a huge way.
One of the major goals of the Juno mission, which began in July 2016 when the probe entered orbit around Jupiter, has been to study the interior of this fascinating gas giant. We can see its amazing cloud tops, sure, but we really didn’t know what’s going on inside.
Well, that all changes as of today. In a series of four papers published today in Nature, and an accompanying News and Views article, the latest results from the spacecraft have been revealed. And, for the first time, we’ve actually got a good idea of what’s happening beneath the cloud tops.
“It’s a first view of how a gas giant planet works on the inside,” Jonathan Fortney from the University of California, Santa Cruz, who penned the News and Views article, told IFLScience.
The four papers are here, here, here, and here. While they focus on different areas of research, they largely have a similar theme – namely relating to some of Jupiter’s key characteristics.
One of the major findings is that we now know how far down Jupiter’s atmosphere extends, 3,000 kilometers (1,860 miles) down from the cloud tops, which is much larger than expected. Once you reach this depth, the composition of the planet changes dramatically.
Much thought had been put into what Jupiter might look like below its clouds. Based on these papers, it appears that at this depth, the interior of the planet changes to behave like a solid – although it’s not actually a solid. Instead, it’s a fluid mixture of hydrogen and helium that rotates like a solid body.
“Our results also show that below those winds of 3,000 kilometers, the planet rotates as a rigid body, and all this information has deep consequences in our understanding on the interior of the planet and in turn it allows us to get closer to understanding its formation,” Yamina Miguel from Leiden University in The Netherlands, one of the authors on the papers, told IFLScience.