Joni Mitchell was right when she wrote the words “We are stardust, we are golden”. We really are star dust!
Where do we come from, and what happens to us when we die? These are questions that have taxed the greatest minds in history. Now science has some answers.
Our bodies are made up of 60 elements including gold, carbon, uranium and arsenic, but where do they come from? Two, hydrogen and helium formed around 300,000 years after the Big Bang. That means the hydrogen in the water you drink has been around since almost the beginning of time. The rest (except lithium, beryllium and boron) were made inside stars in a process called nucleosynthesis. Stars are giant nuclear furnaces made of hydrogen and helium gas. The star’s super-hot core crushes the hydrogen and helium atoms together to make new heavier elements. Think cosmic building blocks. A small star around the size of our Sun, builds smaller elements like nitrogen, oxygen and carbon the basic building block of our cells. To make heavier element you need a larger star. The bigger the star the more effective it is at fusing atoms together, so a giant star like Betelgeuse builds larger substances such as copper, sodium and the calcium we find in our bones, when it explodes in a giant supernova. Even heavier elements like gold form when two giant dead stars called neutron stars collide in an epic explosion. All these elements are blown out into space and are seeded throughout the Universe. 4.6 billion years ago some came together in a giant gas cloud which collapsed to form our Solar System, the planets and eventually us. Some of the elements that make us have passed through many stars during the 13.7 billion year history of the Universe, so atoms in your right hand almost certainly come from a different star from those in your left. Heady, mind-blowing stuff!
Written for Goldie Magazine by Dr Stephen Marsh
Find out what science suggests happens to us when we die, in Goldie Magazine. Coming Spring 2018.
Stephen Marsh BSc, MPhil, PhD, is a polymath artist, sculptor, photographer, musician & scientist.
Forty years of employment has seen him work as a cameraman on Morecambe & Wise, director of Tomorrows World, Executive Producer of Science Broadcasting for BBC, The Discovery Channel & Nat Geo, as well as being a medical researcher & DJ.
At some point he thinks maybe he will find something he is good at.