Everyone should listen to @carolynporco … this alien spaceship stuff is completely out of hand - it’s OVERWHELMINGLY likely to be a lump of ice and rock. We went through similar nonsense with the ‘LHC might create a black hole and destroy the world’ fiasco. There is value in thinking about highly unlikely possibilities of course - and it can be fun to publish a paper or two on them - but some people who are not scientifically / statistically literate really worry about these things when they read about them out of context in the press or on social media.