Juno Science Results Options

[hendric]

https://www.nasa.gov/feature/junoteleconference

Many surprises!

Jupiter not uniform below clouds!

Giant ammonia plume comes up from equator!

Core diffuse, possibly dissolving!

Magnetic field up close has surprised!


Congrats on the amateur images everyone!

[scalbers]

I wonder when models will be able to simulate the patterns and the colors of the clouds. In the (pre-Juno) paper below, figure 5 shows the patterns, though doesn't include the microphysics/chemistry to show things like cloud opacity and colors.

https://www.researchgate.net/publication/25...ian_atmospheres (see figure 5a).

[JRehling]

I've done some recent reading on Juno findings and moreover, tried to illustrate for myself how Juno science has fit into earlier understanding.

One simple kind of framing that is eternally hard to grasp with Jupiter is just how big the planet is and how limited in scope our studies from the top looking down are. Simply put, the Galileo Probe's descent (while instruments were operating) penetrated only 1/450th of the way to Jupiter's center. Juno has revealed that the part of the upper atmosphere that has winds is 3000 km deep – about 20 times the depth of the Galileo Probe's descent, and about 1/25th of the whole planet.

There has been some beautiful work regarding Juno's observed anisotropy of ammonia in the upper atmosphere.

https://www.nasa.gov/feature/jpl/shallow-li...juno-scientists

In retrospect, it seems obvious: When a minority atmospheric component undergoes phase transitions, that allows for mechanisms that can segregate the compound considerably from one place to another (e.g., with water on Earth).

It's also been wonderful that Juno and the end of the Cassini mission provided an almost simultaneous comparison of Jupiter and Saturn and the simple synthesis is that of the three layers in each planet – let's call the upper atmosphere with winds (A), a dense "mantle" of liquid metallic hydrogen (, and whatever core exists, apparently fuzzy in its boundaries ( C ) – Jupiter has a relatively small extent of A and C and is mainly B; Saturn, in contrast, has a much more even division of A, B, and C.

We're still waiting to get an answer on the single question that most motivated Juno – how much core is there? However, the discovery of a fuzzy mantle seems to speak to the formation of Jupiter. This seemingly precludes any origin in which a gigantic rocky-metal core formed first and then the hydrogen-helium atmosphere was pulled from the protoplanetary nebula onto it.

When they announced that an orbiter would be the choice of followup mission for addressing what the Galileo Probe failed to measure, I was skeptical but in retrospect, this was overwhelmingly the right choice. An entry probe could not possibly examine horizontal variations in Jupiter's structure and even with remarkable improvements in depth of penetration could not have probed as deeply as Juno has.

I'm sure there's a lot more Juno science to come. This has really been a wonderful mission even aside from the breathtaking imagery which was never the inspiration for the mission in the first place. Studying the interior of Jupiter is a huge challenge and kudos to the people who conceived of this mission and made it real.

Edit: Here's a nice recent synthesis of work on the deep interior.
https://arxiv.org/pdf/1901.05697.pdf