The European Space Agency’s next large mission will be JUICE, a probe to study Jupiter’s icy moons. People who study other areas of astrophysics (like me) are disappointed that ESA didn’t choose a mission to the stuff we’re terribly excited about. In particular, some people are very disappointed that the X-ray observatory ATHENA lost out.
I don’t really know what should have happened, but this blog post (which I learned about from Peter Coles, by the way) does a pretty good job of explaining why JUICE is interesting.
The most striking thing to me is the extremely long time scale. JUICE isn’t scheduled to get to Jupiter until the 2030s. I know it’s sometimes necessary to plan way in advance, but it does seem like a big gamble to devote a bunch of resources to something that far off. How certain are we that the questions that seem interesting now will still seem interesting then?