Science Behind the Fiction: How a star is really born
Presented by: Cassidy Ward
Last week saw the release of A Star Is Born, a musical romantic drama produced and directed by Bradley Cooper, starring Cooper and Lady Gaga. Based on a 1937 film of the same name, the movie is actually the third remake since the original and tells the story of two singer/songwriters, one established, the other just starting out in the world of professional music.
A Star Is Born is about the birth of a career, but in the wake of its release, we can't help but wonder why we liken celebrities to celestial bodies in the first place. And, for that matter, how stars — the real ones up in the night sky — are actually born?
It's hard to pin down exactly when or why we started referring to beloved celebrities as "stars." There doesn't seem to be a singular moment when usage of the term entered the public lexicon. Instead, it seems, as is common in the evolution of language, to be the result of a slow etymological infection.
Comparisons of humans to heavenly bodies dates back at least to Chaucer, and Shakespeare invokes the comparison in his works on at least one occasion.
The earliest confirmed usage of "star" as a reference to a celebrity occurred in the middle of the 18th century. A 1765 issue of The Gentleman's and London Magazine refers to actor David Garrick in the following way: "The rumor of this bright star appearing in the east flew with the rapidity of lightning through the town, and drew all the theatrical Magi thither to pay their devotions to this new-born son of genius."
This adaptation of language speaks to something innate among humans, a desire to believe we can be more than just animals. The desire for gods and kings is something that lives inside even the most secular among us. This is the psychological niche celebrities fill in the modern world. It's no wonder we've placed them, even if only through language, among the heavens.
A Star Is Born is only the latest in a long line of works exploring our obsession with celebrity. It shows just one way, among many, in which a star can be born. For those of you out there working hard at becoming famous, the methods of ascension can seem murky and intangible, the path to the heavens clouded and unclear. There is no well-trod path to earthly stardom. With that in mind, let us instead focus our attention on the ways in which stars, those that truly glitter throughout the cosmos, are really born.
THE BIG BANG AND THE FIRST STARS
As Carl Sagan famously said in Cosmos, "If you wish to make an apple pie from scratch, you must first invent the universe."
So it is with stars. According to our best estimates, the universe as we understand it began about 13.8 billion years ago. Shortly after the Big Bang, all of existence was a stew of rapidly moving energy, not yet cool enough to become matter. When things cooled a little, that energy slowed down and began to form particles. All of this happened within the first few minutes of the existence of the universe. In fact, there was a brief moment in the early history of the universe when existence, in its entirety, had the conditions like those inside of a star, fusing hydrogen into helium. From a particular point of view, the whole universe was one giant star.
This lasted about 17 minutes, but it took roughly 380,000 years for things to chill out enough for electrons to join the particle party and link up with the protons and neutrons.
Most of that cosmic stew formed into atoms of hydrogen and helium, and that still holds true today. Roughly 99 percent of all matter in the universe is made up of these two elements.
As the universe condensed into a distributed cloud of elementary particles, gravity began pulling them together, initiating a snowball effect that formed larger and larger balls of matter growing hotter and hotter with every particle they gobbled up until finally, light burst forth into the cosmos.
These first stars were likely massive, using up their fuel relatively quickly before burning out or blowing up in fantastic displays of stellar death that seeded the universe with heavy elements and super-massive black holes. These black holes may have been the grains around which galaxies were able to form, setting in motion the building blocks that allowed for the universe as we see it today.
STARS: THE NEXT GENERATION
Despite their seemingly eternal nature, stars do eventually die. The ways in which they meet their end are determined by the way in which they started life. Our sun, Sol, is an average star categorized as a yellow dwarf. It may be the most massive object in our solar system, accounting for more than 99 percent of the mass in the local region, but it's a runt in comparison to some of the truly gargantuan stars floating out there in the vastness of space.
163,000 light years from here, nested in the Tarantula Nebula, is a giant known as RMC 136a1. It has the mass of 315 suns. If that isn't impressive enough — this, the most massive of all known stars, is actually smaller than it once was, having burned off much of its mass during its lifetime.
When it comes to being a star, bigger is not necessarily better. Because of its mass, it's burning through its fuel stores at an alarming rate. While Sol has an estimated life expectancy of approximately 10 billion years, RMC 136a1 is expected to shine for only 5 million.
It's worth noting that while RMC 136a1 is the most massive known star, it isn't the largest in terms of pure size. Which star is deserving of that honor is still up to some debate. But the video below should give you a sense of the scale we're working with. Eventually, RMC 136a1 will explode in a supernova event, scattering its fusion-enriched guts through space before pressing in on itself until it becomes a black hole.
This is the fate of all particularly large stars. While they may not all become black holes, they spend their lives fusing their atoms into more and more complex material, moving up the elemental ladder until they can't fuse any further. When they explode, all of those enriched elements form a new cloud of gas and dust, creating a nebula, the stellar nurseries of the next generation of stars.
This is believed to be the likely origin of our very own sun. Evidenced by the existence of heavy elements like iron on Earth, our solar system must have been born from the violent death throes of a previously massive star.
Like a cosmic fungal spore, the last act of a massive star's life is to toss its pieces out into the void. After a time, gravity works on the debris, bringing it back together until it accretes. Some 5 billion years ago a cloud of gas and dust began swirling together. Most of that matter fell together until fusion began again and the sun was born. But some was left over, forming the planets and other celestial bodies of our solar system, including the Earth and our planetary neighbors.
Sometime later, after the system cooled considerably and the violent forces of our system's early years calmed, life emerged, made of organic molecules constructed from the enriched elements left over after the death of a previous star.
Without this cycle of stellar life and death, humanity could never have looked out upon the vast cosmos and wondered at its origins. We are, in a manner of speaking, the remnants of stars, small pieces of the universe, trying to understand itself.
While we go about our lives, elevating certain members of our species like Lady Gaga and Bradley Cooper to stardom, it might not hurt to remember we all come from the same magnificent origin. Stars, whether heavenly or right here on Earth, have a grand cosmic history. And that's worth celebrating.