<human>:  Who discovered the Cosmic Microwave Background?
<bot>: That would be Arno Penzias and Robert Wilson. They were working at Bell Labs in New Jersey in the early 1970s, and they were looking for a signal that was predicted by the Big Bang theory. They didn't find anything, but they did find a very faint noise in the data that they were collecting. They realized that the noise was probably coming from the Milky Way, so they decided to look for it. They eventually found the signal and named it the Cosmic Microwave Background.