Hello, I just have a quick question about CMB. Why is it from 380,000 years after big bang? Why not before? Will you please tell me if my explantion is right? Before 380,000 years, the universe was too dense to have any neutral atoms (free electrons and protons / plasma). And apparently, these free electrons cause the universe to be opaque (what does this mean? Does this mean energy from light is absorbed? Not allow to be transmitted/or re-emitted?) Because the light is absorbed almost instantly as it is emitted, it is not allowed to move out into space, and can never get to us (travel into the future sort of). Okay if my reasoning is right, does that mean free electrons absorb lights and hold onto it? Whereas, at 380,000 years, atoms are created, and now atoms do not hold the light but let the lights be transmitted through? (Is this because, it only absorbs lights at specific wavelength? and even those that are absorbed, gets re-emitted when electrons come back down to a lower energy orbitals?) Okay, and my last question is, if it started 380,000 years, when did it end?