We’re all familiar with the elements of the period table (thanks in large part to a chemistry class or three), and most of us are especially well-acquainted with some of the most popular elements: We wear gold in our jewelry, fill balloons with helium for all sorts of occasions, and decorate our stores and apartments with flashing neon signs. Yet it’s the elements we don’t think about every day—the ones that make up our concrete, the wires in our cars, and even the salt on our dinner table—that really deserve our attention. In her book, The Elements We Live By, author and physicist Anja Røyne sets out to prove why.
The Elements We Live By, publishing June 9, is a tribute to the unsung heroes of the periodic table—in it, Røyne explains how humanity collects and utilizes the key elements we depend on for life, and why they work the way they do. Her book is filled with everything from why we find plastic in places that humans rarely visit, to which elements allow us to see, how extracting aluminum causes red dust clouds, and even which elements could allow humans to become cyborgs in the future!
To celebrate the publication of The Elements We Live By, we’re sharing an excerpt from the book about the start of it all, and how elements came to exist at the in the universe. Keep reading below!
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The history of the elements stretches back to the birth of the universe. Their story is long—in fact almost incomprehensibly long in relation to human time. To make it a bit easier, I thought I’d take the creation myth of Genesis as inspiration and tell the history of the world in seven days.
In this story, I’ll turn 1 billion years into half a day, 1 million years into 45 seconds, and 1,000 years will be covered in 0.44 seconds. It’s been 13.8 billion years since the universe was born, but in this account, time began when the clock struck midnight on Monday morning.
Monday: The Birth of the Universe
At first, there was neither time nor space. How and why everything got started is complicated—but we know that it all started with a bang. The explosion we’ve come to know as the big bang flung the energy in the newborn universe out in all directions. After this chaotic start, the young universe started to be governed by the laws of nature we know from our world today.
Just as the dust in my house gathers into dust bunnies (it’s just a matter of giving it enough time!), the energy in the universe eventually started clumping together. These clumps, or particles of energy, are what we call mass: matter, substance, that which is tangible, that which makes up everything you could potentially touch and feel in the universe.
My body, my belongings, and the planet we live on—absolutely everything we surround ourselves with is made up of atoms. Atoms are composed of three types of particles: protons, neutrons, and electrons. The protons and neutrons are firmly stuck together in the atom’s nucleus, and the number of protons in the nucleus is what determines which element the atom is. If the nucleus were to get rid of some protons or receive some new ones, the atom would become a different element. Initially, an atom has the same number of protons and electrons, but the electrons are whirring around the outer edge and can be exchanged between atoms in what we call chemical reactions.
Protons, neutrons, and electrons arose in the glowing soup of energy and mass that made up the young universe. Protons and neutrons ended up sticking together and becoming atomic nuclei in the elements hydrogen, helium, and lithium. These smallest and lightest elements have one, two, and three proteins in their nuclei, respectively. Today, hydrogen is an important building block in water and in the organic molecules that make up living beings. Take the human body, for example, which is made up of almost 10 percent hydrogen. When you think of it that way, you could technically say that you come directly from the birth of the universe!
Sixteen seconds past midnight, the universe had gotten so cold that electrons could attach to atomic nuclei without being released immediately. So, for the very first time, it was possible for light to move through the universe without being stopped by hot electrons. At just past midnight, there was visible light in the universe—even though there was no one there to see it.
Over the course of the next twelve hours, the mass in the universe continued clumping together. Huge clouds of atoms were formed, and before the clock struck three in the morning, groups of these clouds had become the very first galaxies. One of these galaxies turned out to be the Milky Way—our home. Today, the Milky Way is just one of more than two thousand billion galaxies in the universe.
At 6:00 am, some of the atom clouds in the galaxies had become so big that they collapsed beneath their own weight. This is how the first stars came to be. In one of these—a clump of material that was considerably larger than our own sun is today—were the hydrogen atoms that would be transformed into the oxygen you just inhaled.
The weight of all the surrounding atoms pressed these hydrogen atoms against each other with enormous force. First, this caused the electrons to detach from the nuclei. The pressure then became so intense that it caused the hydrogen nuclei to fuse together and form new helium nuclei. This fusion released huge amounts of energy that warmed up the clump of atoms, making it a bright star. The same process is still taking place today in our own sun; the light that meets your eyes when you look outside your window comes from atomic nuclei fusing within the sun’s interior.
As most of the hydrogen nuclei gradually became helium, the release of energy in the star’s interior started to slow down. The center of the star no longer had enough power to withstand the pressure from the surrounding material, and it collapsed. This started a new phase of the star’s life. The collapse forced the helium nuclei so close together that they fused in new reactions. Three helium nuclei with two protons each became a nucleus with six protons—which is carbon. Then, the carbon nucleus fused with yet another helium nucleus to form a nucleus of eight protons. This is oxygen, and this atomic nucleus can be found at this very moment in an oxygen atom inside a red blood cell on its way to your brain.
Inside the star, the process of fusing atomic nuclei into heavier and heavier elements continued. Eighty-six percent of your body is made up of carbon, nitrogen, and oxygen, all of which were formed during this phase. Here on Earth, the pressure is far too low to make such elements, so we can be sure that these building blocks in our bodies actually did come from stars. We are stellar beings—every single one of us! In addition, the iron in our blood, the phosphate in our skeletons and DNA, the aluminum in our mobile phones, and the salt (sodium and chloride) we sprinkle on our food were all made during this phase.
A few minutes into the weeklong story, the star’s life is over, ending with an explosion so spectacular that it got the name “supernova.” In the explosion, elements even heavier than iron were formed—including nickel, copper, and zinc. The power lines in your house are made of materials from a supernova.
The leftovers from the explosion—the material that was not thrown into space, that is—collapsed and became a neutron star. In a neutron star, all of the nuclei have fused together into a massive clump the size of a large city (about 10 miles/15 kilometers in diameter), and, in a way, it really is an enormous nucleus, even though we don’t call it an element. There are about one billion neutron stars here in our own galaxy, but since they’re so small and cold compared to the other stars, it’s not easy to spot them.
When I think about how much space there is in the universe and how small neutron stars are, I feel like what happened next seems almost infinitely impossible. All the same, we know that it had to have happened. At some point during the first days of the universe, two neutron stars collided. This collision created gold, silver, platinum, uranium, and a host of other elements so heavy that they can only be formed in such extreme events. The newborn elements were cast out into space and mixed with clouds of dust and atoms in the galaxy.
And that’s how elements came about on the first of seven days. Elements are still being created out in the universe as stars are being born and dying, exploding, and colliding all the time. Here on Earth, however, the elements are fairly constant. It’s only through radioactive processes in which unstable nuclei of uranium and other heavy elements sometimes start splitting up that elements are created and destroyed on our planet. Even in laboratories, it’s almost impossible to recreate the processes that take place inside stars. We have almost endless opportunities to create materials by varying how we assemble elements, but when it comes to the elements themselves—what we’ve got is what we’ve got.
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To read about the next six days of the universe’s creation, pick up your copy of The Elements We Live By by Anja Røyne, available June 9! It’s a perfect read for anyone curious about the world we live in—and what that world might look like in the future.
