This thing is -270°C and is EVERYWHERE

How do we know we are not detecting the atmosphere of the heliosphere itself?

Edit: I would love to see a video on the redshift theory that astronomers rely so heavily upon. The discrepancies in the detection of other EMR spectrum that do not correlate with the redshift analysis warrants further attention. Without finding a remedy, we should question the very notion of the accepted theories. 
P.S. Yes, I am a Big Bang sceptic.
Thank you.