3. The Emanating Brilliance of Stars

What are stars? How are they birthed? And what is a supernova explosion?

This episode features a two-part conversation on the emanating brilliance of stars.  First, we learn from Joel Primack, a distinguished professor of physics at the University of California in Santa Cruz.  Next, we sit down again with Todd Duncan, a cosmologist whose work is guided by the theme to better understand how a cosmic perspective gives our human experience a larger context of meaning.

In this conversation, we explore the emergence and death of stars.  We will trace the elements found in all life on Earth, including those found in our bodies, back to supernova explosions.

Throughout history, human's have been moved by the emanating brilliance of the stars. We have organized our lives around them.  We've even organized entire civilizations around their beauty and order.

Here's the essence of the universe story. The stars are our ancestors. Out of them, everything comes forth. Stars are dynamic entities. They're born, they develop, they even die.

Star birth occurs when gravity squeeze together a cloud of atoms so tightly that nuclear fusion ignites in the center. In the process, hydrogen fuses into helium. This nuclear energy expands outwards and opposes gravity. So stars represent an amazingly creative balance between the powers of gravitational collapse and nuclear explosion.

Once a star's nuclear fuel is spent, there is nothing left to prevent gravity from collapsing inwards.  Causing the death spiral to begin. This super-concentrated dot of matter, which we call a supernova, explodes outward with the power of a 100 billion stars. As it expands, it creates all the elements: phosphorous, oxygen, carbon, gold. These are spewed out into the Milky Way Galaxy and then the whole process starts again. They drift as a cloud, and then they collapse, give birth to a star, and other celestial bodies like our planet, the Earth.

It is by this stupendous process that we can say that the stars are our ancestors.

Learn more about the wonder of the stars in our podcast with Joel Primack and Todd Duncan.

To dive deeper into the story of the universe, enroll in one of our free online courses here, created with Yale University.

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