I love the summertime. Looking forward to barbeques, lemonade, and sunshine is what gets me through dreadful Edmonton winters, but my favorite part of summer is driving out to the country in a flatbed truck, and spending nights just gazing up at the twinkling lights in the dark sky. Something about lying under the stars sparks my curiosity, wondering about the world, its problems, and particularly my understanding of where I sit in the universe. I’ve been faced with a lot of trials recently, and can’t help but wonder how it all fits into the puzzle that is the great wide open of the cosmos that surround us.
Carl Sagan, a great astrophysicist, once stated “we are made of star stuff”. I’ve always found this statement to be empowering, as though he meant that as people, we have a light and personality that sparkle like the glowing orbs in the night sky. Although poetic, Dr. Sagan’s meaning was also much more literal. The elements that make up our DNA, cells, and body structures, such as carbon, nitrogen, iron, and calcium, are all elements that at one point were created within stars. How could we possibly be made of the same things as those bright burning objects in space, you say? Well, it all goes back to the cycle of life, and this time, the cycle of the first star’s life.
Many mysteries surround the birth of the first star. Of course, no one was present to witness the event – how could we be? The elements we are made of weren’t even present yet. But through many computer simulations and an understanding of how stars form in our universe today, scientists have been able to speculate on how the bright specs in our night sky came to be. About 14 billion years ago, the Big Bang resulted in the creation of only two elements in our universe, hydrogen and helium. For the longest time, these elements, along with dark matter, were all that existed. Eventually though, the matter and elements began to interact and collapse through the atoms’ nuclei producing gravitational pulls, forming a clump of gas and matter called a protostar. Through a process called nucleosynthesis, this interaction resulted in the fusion of light hydrogen atoms into heavier helium, producing energy and the star’s first shiny visible debut. As the star’s core became hotter with the energy from the fusion, it was soon able to absorb surrounding gas and matter and become larger. After millions of years of absorbing hydrogen and converting it to helium, the star began to run out of energy and cool. This caused the gravitational pull to change abruptly and the outer layers of the star to no longer be drawn inward. This can result in a supernova explosion, or a gradual release of the elements within the star. Either way, heavier elements than were previously available were created and made available for use in the establishment of new protostars. Gradually, the fusion of different atoms formed heavier and heavier elements and eventually produced the elements common on our planet today.
Now, although this explanation doesn’t go further to outline how we, our planet, or even our galaxy formed, it does provide a framework for how the building blocks of everything around us came to be. What Carl Sagan didn’t say was that to “be made of star stuff”, the stars had to undergo trials themselves. The formation of the first star in particular is the epitome of the creation of something out of nothing. It is an inspiring story and something to remember – how in the face of all darkness, heat, pressure, and stress can lead to a bright and beautiful light. And personally, I am inspired and honoured to be the product of that star adversity.
Image CC The Smithsonian on Flickr