We see objects either because they emit light [particle or energy] toward us or because light bounces off them in our direction. This is true for all energy not just visible spectrum. We see stars because they emit light towards us and nebula because it is, generally, illuminated by some stellar light source. These emit light in all directions and we see the light heading our way. The CMB was released very early and, as I have heard it explained, has red shifted so far it is in the microwave spectrum as it moves "away" in all directions. If its moving "away" how do we actually see it ? If by way of answer its explained that in some sense part is heading toward us allowing us to see it why is it still shifted to the microwave end of things. I'm sure this is answered somewhere I simply have not run across it yet.