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Turbulence in Saturn's Atmosphere
neutron_p writes "Today an image of turbulence in the atmosphere of Saturn has been unveiled. This image was taken with the NASA/ESA/ASI Cassini-Huygens spacecraft camera. This pattern is an example of a 'Kelvin-Helmholtz instability', which occurs when two fluids of different density flow past each other at different speeds. This phenomenon should be common on the gas-giant planets."
I'm not sure how it's news, as it should generally be anticipated to occur naturally in gas giants, as mentioned in the article. There is a scant possibility that the phenomenon has not been observed before, or perhaps only observed in a very specific subset of conditions, which would lead to questions as to whether our understanding of the nature of gas giants is really valid.h tml and if you find anything new and exciting, there's a very small wikipedia stub that could use expanding.
The whole thing should really only be of interest to academics interested in this specific detail of thermodynamics. I don't see any practical reason why a lay person should care. Anyway, for a little more info on this, you can read http://www-sccm.stanford.edu/Students/witting/kh.
wouldnt we get better performance long-term from a larger number of smaller probes?
Most of the cost goes into getting to these very far away places and holding enough propellent that you can slow down enough to be captured into orbit after you've been going very fast for a few years. It's not feasible to launch probes to outer planets all the time because you lose the ability to "sling shot" past other planets as a cheap way to pick up a lot of speed. These gravity assist (or more accuratley, angular momentum assist) moves make a little ship go whole heck of a lot faster which means you don't need as much propellent to get you somewhere. You have to go really fast to someplace that several billion miles away in a few years.
and hence would have more up-to-date sensors. For example, the CCD on the Cassini camera is only 1 megapixel!
The way to get better quality pics is NOT to have more pixels but to have better optics. The cameras in the "eyes" of the Mars Exploration Rovers (the pancam) are only about 1 megapixel and they have returned VERY high resolution pics that look great if you have to blow them up 10 times their size. That's because NASA spends a lot of money to use phenomonally good optics. In addition, more megapixels means larger files which requires higher data transfer rates which requires more power to your antenna which means less electricity to do other stuff. (whew)
I have heard it suggested that most of the useful function of the JIMO $10 billion orbiter could be done with a simpler $1 billion direct-to-europa mission.. And look at New Horizons, with a mission cost less $1 billion, or SMART-1 less than $100 million..
Dude, compare apples to apples here. SMART-1 is a test of new technology (ion drive) that is meant to see how well it works and if it useable in other missions. It was meant to be a cheap way to get to the moon. You don't need a whole lot of force to get the moon and orbit it if you're willing to wait a few years...like SMART is. To get to Jupiter and then ORBIT it, you have to go very fast to get there, then be strong enough to slow down to be captured into orbit. Then maybe you'd want a few kilos of propellent left to actually move around near Jupiter for a few year. That is a completely different scope than crusing along to the moon for several years or flying by Pluto-Charon before the atmosphere freezes out.
Quite an impressive animation. I want one on a a globe. :)