h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

 It is widely debated throughout the galaxy whether or not Colossus is the biggest planet, or, if it isn’t, what is. The reason it is such a wonder is that since so many people come to see Colossus because of the sheer size of it, in the midst of the chaos nobody can get a permit to measure the circumference of the planet. If one could get a permit, one of two things would be most likely to happen. They would either forget completely how to do it, or just stop caring at all. If one actually could figure out how to do it, it would be highly unlikely that he or she would be able to actually do it, and even if someone got so far as actually physically doing it, they wouldn’t be able to publish their findings. Even if they could, well, not everyone would believe them. And so remains the mystery.