Astronomy Cast Ep. 620: Why Getting to the Outer Worlds is So Difficult by Fraser Cain & Dr. Pamela Gay Good News! Over the next few years we’re gonna see a flotilla of new missions headed to Jupiter and Saturn. Why aren’t we seeing more missions to the outer planets like Uranus and Neptune, even Pluto? It turns out those places are far away. Today let’s talk about the challenges of exploring the outer, outer solar system.