I thought it was because as they reach our level of civilisation, they built giant particle accelerators for research and turned their planets into black holes.
I think it would be hilarious if an alien civilization flew into our solar system only to find a black hole -- complete with moon -- orbiting the sun between Venus and Mars! No doubt they'll know exactly what happened...
hahaha, you should work for Hollywood!
Somebody get me Pauly Shore on the phone!
The mission will focus on Jupiter's structure and evolution, and not on Europa or the other icy moons that may hide oceans under their surfaces - a disappointment if you ask me.
... especially since we could be using those icy moons as giant particle detectors (PDF) for neutrinos and other cosmic rays.
Live within your income, even if you have to borrow to do so. -- Josh Billings