The story starts with a bang
You may already know that the matter making up everything you have ever touched, smelled, or seen came from the Big Bang, which unzipped the universe 13.8 billion years ago. The Big Bang theory is the prevailing model of how the universe was created. It suggests that everything—all matter and energy—was jammed into a tiny point that became the universe in a massive explosion that marked the beginning of time and the creation of space itself.
At first, gold was not even a shimmery speck in the universe’s explosive debut. After the Big Bang, enormous quantities of protons, neutrons, and electrons combined to form hydrogen, helium, and a little bit of lithium, says Imre Bartos, an astrophysicist at the University of Florida. These reactions seeded the universe with this cosmic dust for hundreds of thousands of years.
For the most part, these elements were evenly distributed across the universe. But every now and then, the density in one place was a little bit higher than the density everywhere else. When this happened, gravity began pulling atoms closer together into swirling clumps of gas and dust. As a clump compressed, its center would become dense and hot enough to start fusing hydrogen nuclei—that is, protons—together, releasing energy, and giving rise to a new star.
According to scientists’ best estimates, stars began forming 13.6 billion years ago, 200 million years after the Big Bang. Gold was still nowhere to be seen.
But several billion years after the first stars were born, an important pair of large stars, each about 10 times the mass of the sun, formed and started circling each other, creating a binary star system. Bartos and a collaborator, Szabolcs Márka at Columbia University, identified the stars in 2019, publishing their work in the scientific journal Nature. These unnamed stars might have played a crucial role in the formation of Earth—and the precious resources, including gold, deep within our planet.