A man reads a comic then writes a program based on it.
As a repository for all human knowledge, Google must be able to see the future, or at least have as good of an idea of what's going to happen as the combination of everyone who posts stuff online. xkcd put this to the test by Googling variations of "by the year...," and while the good news is that we'll be immortal by 2040, the bad news is that the world's gonna end in 2012.
Here's a handy chart from Randall Munroe and web comic xkcd detailing how much radiation you get from different common sources. Fun fact: eating one single banana gives you a higher dose of radiation than living 50 miles from a (functional) nuclear power plant for a year.