The CMB is a uniform 2.725 Kelvin , but the tiny fluctuations (one part in 100,000) are what grew into galaxies. Visual Hook
How 380,000 years of chaos became the blueprint for the cosmos. The Core Narrative Precision cosmology : the first half million years
Based on this era, we know the universe is roughly 68% Dark Energy, 27% Dark Matter, and only 5% "stuff" (atoms, stars, us). The CMB is a uniform 2
Start with the moment of "last scattering." Before 380,000 years, the universe was a hot, opaque plasma soup. Then, it cooled enough for atoms to form, the fog lifted, and light finally escaped. This is the CMB —the oldest "picture" we have. 27% Dark Matter