What's the human body made of? Ninety-nine percent consists of atoms of just six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus, with the remaining one percent consisting of trace elements like magnesium, sulfur, and iron.
But where did those elements come from? That question long presented a puzzle to scientists. At least it did until the publication of a now-obscure scientific paper in the middle of the twentieth century, as celebrated astrophysicist Neil deGrasse Tyson explains in a new video (above).
"There was a seminal paper -- one of the most important research papers ever published -- that gave us the description of the origin of the elements," Tyson says in the video.
The paper is entitled "Synthesis of the Elements in Stars" but is sometimes referred to as the BFH paper, after the authors' initials. It was published in Reviews of Modern Physics in 1957. Before its publication, the prevailing theory held that all elements were products of the Big Bang 15 billion years ago. But this theory accounted only for light elements like hydrogen and helium.
So where did the heavy elements found in nature come from?
The BFH paper argued that all heavy elements were created within stars via nuclear fusion -- a process known as stellar nucleosynthesis. As stars cool and "die," they release the heavy elements into space. Ultimately, some of this material is incorporated into planets and even our bodies.
If the paper was so important, why do so few nonscientists know about it? According to Tyson, it's because the paper's origins don't fit conventional notions of scientific discovery.
"There was no lone scientist burning the midnight oil making the eureka discovery," Tyson says. "It was a little messier than that. But the consequences of it are profound."