It seems that we will need more than one mission per planet for scientists to uncover the mysteries of Jupiter and Saturn.
That is the conclusion about the enigmas that NASA’s Cassini and Juno missions have revealed thanks to new data received on Earth.
Cassini ended its 13 years on Saturn in September 2017; Juno recently passed the midpoint in their orbits of Jupiter. Both missions have produced incredible data on the detailed workings of the two gas giants, and scientists have been working hard to interpret all that information.
” While there are puzzles yet to be explained, this is already clearing up some of our ideas about how planets form, how magnetic fields work, and how winds blow,” says David Stevenson, a Caltech planetary scientist, in a university statement. . along with his presentation at this week’s meeting of the American Physical Society in Boston, USA.
Stevenson focuses especially on data from the Juno spacecraft, which has been on Jupiter for two and a half years. In these months the probe has found a large number of unexpected phenomena in the gas giant, including strange strengths and weaknesses in the planet’s magnetic field and heavy elements distributed throughout the planet.
Fortunately, the spacecraft has more than two years to live, and scientists are still carefully studying the data collected by its predecessor on Saturn.
“A successful mission is one that surprises us. Science would be boring if it just confirmed what we previously thought,” Stevenson said.
What has this latest data revealed?
Gravity and magnetic sensors aboard the Juno spacecraft have discovered that the magnetic field of this gaseous planet has spots (regions of abnormally high or low magnetic field) as well as a significant difference between the northern and southern hemispheres.
“It’s unlike anything we’ve seen before,” Stevenson clarifies.
Gravity data has confirmed that in the middle of Jupiter, which is at least 90% hydrogen and helium by mass, there are heavier elements that represent more than 10 times the mass of Earth, but they are not concentrated in a nucleus, but which combine with the higher hydrogen.
Regarding the outer zones, the abundance of heavier elements in this zone is unknown, but it is clear that they play a greater role than expected in the generation of the magnetic fields of both Jupiter and Saturn. More research is needed, because Juno’s microwave sensor showed that the atmosphere is uniformly mixed, something not predicted by current theory . “Any explanation for this has to be unorthodox,” says Stevenson.
Referencia: The 2019 APS March Meeting presentation “What Juno and Cassini have told us about Giant Planet interiors,” by David Stevenson, will take place Wednesday, March 6, at 2:30 p.m. in room 258C of the Boston Convention and Exhibition Center. Abstract: meetings.aps.org/Meeting/MAR19/Session/P62.1
