Cosmic Dawn: How the First Stars Lit the Universe

In October 2026 a Hubble study in Nature Astronomy reported that nearby galaxies with the strongest supernova winds let the least ionising light escape, a new clue to how the early universe cleared. This film explains the fundamentals: how the first light was set free 380,000 years after the Big Bang, the dark ages that followed, the first stars and galaxies, how their ultraviolet light broke hydrogen atoms apart and blew bubbles that merged, how quasar light and the microwave background show when it happened, and what is still unknown.

From the dark ages to a clear sky

How the first stars lit the universe.

First light

When light first flew free.

The first stars

Giants made of pure hydrogen and helium.

Lifting the fog

Breaking hydrogen apart.

Reading the fog

A shadow in the light of quasars.

Who did it?

The suspects, and a light budget.

Listening for hydrogen

A map of the fog itself.

A clear sky

What we know, and what we don’t.

Read the full story as text · อ่านภาษาไทย

This interactive 3D film needs JavaScript. PlanetPast home