the first secondReputable sourceWell documented
The First Matter
On the timeline · around the first second · The First Instants
What happened
Within the first second, the searing universe cooled just enough for quarks to bind together into protons and neutrons — the particles that sit at the heart of every atom.
Why it matters
The ordinary matter that would one day make up stars, planets and people first came into being in this instant.
Sources
- NASA. Cosmic History · Reputable source