From Star Stuff takes its title from Carl Sagan’s monolog at the opening of “Cosmos: a Personal Voyage”. The 1980’s television show covers a range of scientific subjects from the origin of life to the birth of the universe. This show played a significant role in my lifelong fascination with science and humanities place in the universe. From Star Stuff traces the journey of a photon. From the formation of the star, bouncing through the core, flying through space, and finally being absorbed into the life cycle of earth. The following is Dr. Carl Sagan’s monolog.

“The lives and deaths of the stars seem impossibly remote from human experience and yet we’re related in the most intimate way to their lifecycles. The very matter that makes us up was generated long ago and far away in red giant stars. A blade of grass, as Walt Whitman said, is the journey work of the stars. The formation of the solar system may have been triggered by a nearby supernova explosion. After the Sun turned on, its ultraviolet light poured into our atmosphere, its warmth generated lightning, and these energy sources sparks the origin of life. Plants harvest sunlight converting solar into chemical energy. We and the other animals are parasites on the plants. So we are, all of us, solar-powered. The evolution of life is driven by mutations, they're caused partly by natural radioactivity and cosmic rays, but they're both generative in the spectacular deaths of massive stars thousands of light-years distant.

Think of the sun's heat on your upturned face on a cloudless summer's day. From a hundred and fifty million kilometers away we recognize its power. What would we feel on its seething self-luminous surface or immersed in its heart of nuclear fire? And yet, the Sun is an ordinary even a mediocre star. Our ancestors worshiped the Sun and they were far from foolish it makes good sense to revere the sun and the stars because we are their children.

We have witnessed the life cycles of the stars. They are born they mature and then they die. As time goes on there are more white dwarfs, more neutron stars, more black holes. The remains of the stars accumulate as the eons pass. But interstellar space also becomes progressively enriched in heavy elements out of which form new generations of stars, and planets, life, and intelligence. The events in one star can influence a world halfway across the galaxy and a billion years in the future”

“The cosmos is within us. We are made of star stuff. We are a way for the universe to know itself.”

― Carl Sagan

Level: Intermediate/Advanced

Duration: 8 min.