There’s been much discussion about the possibility of the origin of life on Earth being outside our solar system lately, and that’s one of the goals of the New Horizons mission.
Aside from being the first probe to actually visit Pluto (50 days till the half way point; 1780 days to go!) its secondary mission is to scout out, and hopefully flyby some Kuiper belt objects. (The Kuiper belt is the area where Pluto and other dwarf planets are found. It is believed that there are many thousand objects in that area, totaling around the mass of Earth.) It is from here that some of the local comets could come from (recent research points to the much further out and sparser Scattered disc being the source of most), and some believe that on these are ancient microbes. (It’s possible that Pluto could too; this is to be tested.)
These ideas have been given some strong support recently; on the ISS there was a recent experiment where some microbe samples were placed outside the station and given no protection. (The Van Allen belt would have offered some protection, but I digress.) 553 days later they were brought in…
…and some were still alive! It does make me wonder; if life can continue in space then why not Mars or Jupiter? Maybe the spacecraft hunting worm from Star Wars: The Empire Strikes Back isn’t so implausible afterall!