The mysterious Wow! signal could have come from a civilisation moving to a new star system 'aboard' a free-flying planet - dark and almost invisible.
No star can glow forever, endlessly maintaining stable conditions on its planets. A civilisation that manages to survive and evolve long enough will sooner or later run into this problem and will need to 'relocate' to a new suitable location. Science fiction often builds huge interstellar ships for this purpose, but you can generally get by with a more economical means of transportation - free-flying planets... →
