ACEIZE

Several stages of building the Pioneer rockets were not done in a clean room. The result is that it is likely that bacteria is present on the outer shell of the Pioneer probes. As these probes head towards the outer rim of the solar system and beyond, they will carry the earthly DNA in that bacteria through the galaxy. The article makes it clear that these probes will not be near another star system for some time (more than 40,000 years), and that it is not likely that they will get anywhere near another planet for a long time. Still, score one for migration. DNA and children first!