Comment Moving planets (Score 1) 519
There's not really any conceivable way to do any such thing, nor any purpose which would be best served by it, and other side effects of that much energy expenditure would be of far more immediate concern. If my math is right, the energy required to move Mars to Earth orbit would be about 20x its gravitational binding energy. You probably don't want to just give it a big whack, and the list of things that would probably be easier would probably include disassembling the planet and moving it to a new orbit piecemeal.