You are probably going to ask more about CMB...

"Actually, I was not going to"

I will tell you anyways. The CMB is oval because no one can take a sphere and make it flat without tearing it. The CMB originally had short wavelengths and as the Universe has expanded, light was stretched into longer and less energetic wavelengths.It is also an excellent predictor for the Big Bang because it has accurate size and types of anistropies in the CMB as well as it's black body spectrum. Anistropies correspond it areas of varying density fluctuations in the early universe. On the map, red represents hot and blue represents cold.

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