Photolysed Atmospheres?
Hi Guys
The organics find is not unexpected since many have argued that's what makes Callisto so dark. Question is: where is it from? A thin trickle of comet debris? A photolysed primordial atmosphere? Or sub-surface exudations?
Callisto seems to have little tectonic resurfacing, but Ganymede has been pretty active at some time, and Europa is... Europa.
We won't know more until we go...
Adam