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3. Stars & Elements
By 200 million years after the Big Bang, the Universe had become a very dark and cold place. Then things started to change. First, galaxies and nebulae formed. These were the earliest structures in the Universe. Then stars – “hot spots” of light and energy – emerged from these clouds of dust and gas.

3.0 Stars and big history

With the birth of the first stars, a fantastic chain of events occurred that made possible a diversity of elements and chemistry. Anything was possible.

3.1 How were stars formed?

Ever spill jelly beans on the floor? In the new Universe, some atoms – like the jelly beans – wound up together in pockets. Unlike the jelly bean scenario, gravity did its thing. Long story short…stars.

3.2 What did stars give us?

Aging and dying stars get hotter than… well, they get hot. Hot enough to create new, heavier elements. What's so special about the heavier elements? Imagine life without metal.

3.3 Ways of knowing: Stars and elements

All those new elements. What exactly were they and how did they bind to or repel each other? The science of chemistry was born as early scientists studied the properties and structure of chemical elements and compounds.

Practice and feedback

Test your Unit 3 knowledge and skills! Investigate how new points of view pave the way for progress, and take the Unit 3 quiz and glossary challenge.