WHAT IF you still had so many more strange questions about the universe? And what if Randall Munroe, former NASA roboticist and xkcd creator, were prepared to move mountains, eat clouds and fill the solar system with soup to answer them? Whatever your hypothetical query, whether it's how to make a lava lamp out of lava or how many inhabitants of New York it would take to feed a T. Rex, here is a practical guide to the weird, wonderful (and sometimes terrifying) world of WHAT IF? 2
