For years I've been fascinated by the ingenuity of rocket scientists and space navigators who came up with a brilliant idea that made long-distance interplanetary travel possible. For the benefit of the straight shooters, it is virtually impossible to deliver a space craft on chemical fuel alone anywhere further than Jupiter, and even that is a great challenge. That is, if you point your rocket right at the target and shoot - like they do in the military. Burn your fuel, accelerate that baby to the limit, and watch it fall short of the target. Such is physics. But these guys found a way out - swing by one of the planets nearby, and steal some of its energy! That's how they shot Voyagers way out of the Solar System. That's also how they saved the Galileo mission - by getting the spacecraft first to Venus (who would have thought!), then back to Earth, and even that was not enough - a couple of years later it fell right back towards the Mother Earth, swinging by a hair from it
