It seems as though every man and his dog is trying to land something on a planet, asteroid, or rock millions of miles away from Earth nowadays. One of the most recent escapades has been to Pluto, and before that scientists flexed their muscles by landing a probe on a comet. What has this got to do with The Walking Dead? Well, scientists are always looking for life, and where there is life, there is potential for disease. Some fans have gone as far as claiming that the virus that sparked the outbreak was in fact brought back from a space exploration mission. it could've been kept as classified information, and as a result nobody can explain the cause.