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NASA Spacecraft Reveals Jupiter's Interior In Unprecedented Detail (theguardian.com)
NASA's Juno spacecraft has revealed that Jupiter's iconic striped bands, caused by immensely powerful winds, extend to a depth of about 3,000km below the surface. The findings also provide a partial answer to the question of whether the planet has a core, "showing that the inner 96% of the planet rotates 'as a solid body,' even though technically it is composed of an extraordinarily dense mixture of hydrogen and helium gas," reports The Guardian. From the report: The findings are published in four separate papers in the journal Nature, describing the planet's gravitational field (surprisingly asymmetrical), atmospheric flows, interior composition and polar cyclones. A crucial question was whether the bands on Jupiter, caused by air currents that are five times as strong as the most powerful hurricanes on Earth, were a "weather" phenomenon comparable to the Earth's jet streams or part of a deep-seated convection system. Juno's latest observations point to the latter, showing the jets continued to around 3,000km beneath the surface -- deep enough to cause ripples and asymmetries in the planet's gravitational field that were perceptible to detectors on the spacecraft. On Earth, the atmosphere represents about a millionth of the mass of the whole planet. The latest work suggests that on Jupiter the figure is closer to 1%. The new findings, based on extremely sensitive gravitational measurements, also begin to paint a picture of the internal structure of the planet.
These articles are among the best on Slashdot. With me not following Astronomy-related news closely, but having an interest in Astronomy, they're always very welcome and nice surprises.
...gis sdrawkcab (usually not responding to ACs; don't bother posting as AC)
3 of the 4 papers are based on results of instruments other than the Juno am, and putting a better visual camera on there would not have improved the results (including many of the pretty pictures too). There was some serious concern about guaranteeing the lifetime of the camera too due to radiation. So putting a better camera on there, which would also mean budgeting more for the use of the data, and budgeting more for hardening of that camera, would mean making cut backs on the other instruments. Other instruments like imaging spectrometers (which also produce some pretty pictures...) the gravity measurements were there to answer some current big questions about the interior composition of Jupiter, coincidentally a big part of the results in TFA.
With space probes, you can choose to get more of the same data as you've gotten before to refine previous answers to questions or to get new data to answer questions with almost no answers. The Juno design pushes much more to the latter for their given budget. The JunoCam is then a minor equipment risk without the larger budget risk involved in making it a major science instrument with better performance guarantees.