The Bedtime Scientist

A question

How are stars born?

A calm, true answer. Then, if the wondering keeps going, the whole episode.

The short answer

Gravity, given long enough. A nebula is a cloud of gas and dust light-years across, cold and drifting, and gravity slowly gathers its thickest parts inward.

As the middle grows denser it grows hotter, until it is hot enough for hydrogen to begin fusing, and the cloud lights from the inside. Our own Sun was born that way, probably alongside thousands of brothers and sisters that have long since drifted apart.

Go deeper tonight

Nebula Nurseries: How Stars Are Born

The full episode, in one calm voice, with nothing that startles.

The episode

Nebula Nurseries: How Stars Are Born

0:00 11:57
Sleep timer

Read the guide for this one in the morning.

This connects to

Gravity Heat and energy Deep time

One idea turns up in many different nights. Follow one and the library starts to join up.