Extras

Video thumbnail: Breakthrough: The Ideas That Changed the World Discovering the Big Bang

Breakthrough: The Ideas That Changed the World

Discovering the Big Bang

In 1923, Edwin Hubble began the manual process of photographing the Andromeda Nebula.

Discovering the Big Bang

Video thumbnail: Breakthrough: The Ideas That Changed the World How Far Are the Stars?

Breakthrough: The Ideas That Changed the World

How Far Are the Stars?

How a New York property boom led to the discovery of the distance to the stars.

How Far Are the Stars?

Video thumbnail: Breakthrough: The Ideas That Changed the World Glass - A New Wonder Material

Breakthrough: The Ideas That Changed the World

Glass - A New Wonder Material

Learn how clear glass was born - and gave us spectacles almost 800 years ago.

Glass - A New Wonder Material