Precision Cosmology : The First Half Million Years Page

Contrast the "guesswork" of 20th-century astronomy with modern missions like Planck . We’ve moved from "the universe is roughly 10–20 billion years old" to "it is exactly 13.787 ± 0.020 billion years old." Key "Stats" to Highlight

How 380,000 years of chaos became the blueprint for the cosmos. The Core Narrative Precision cosmology : the first half million years

The CMB is a uniform 2.725 Kelvin , but the tiny fluctuations (one part in 100,000) are what grew into galaxies. Visual Hook 27% Dark Matter

A "timeline of transparency"—showing the transition from a glowing orange wall of plasma to the first streaks of clear light, eventually fading into the "Dark Ages" before the first stars turned on. and only 5% "stuff" (atoms

Based on this era, we know the universe is roughly 68% Dark Energy, 27% Dark Matter, and only 5% "stuff" (atoms, stars, us).