I was catching up on some articles, and then I ran across something I nearly forgotten about ... ion engines.  This had made news a while back but not much had hit any media outlets, least none that I heard.  I roughly know how the they worked, but nothing more than a curious laymen.  I came across an this article from iflscience.com and now I am going to go back and do more reading on it.  In case you do not click on the link, it is about the Ion engine, the satellite Dawn and the Dwarf Planet Ceres.