Today’s theme for the final day of the little advent exercise is “Light.”
We now know that what we call light is just one part of the range of radiating energy, and that energy and “matter” are facets of the same thing. We also know that the atoms of our matter, the vast majority of what we touch, see, smell around us every day, was forged in the heart of stars; for us to exist, earlier generations of stars had to be born, live, age, and die. Here is how Carl Sagan put it:
Our Sun is a second- or third-generation star. All of the rocky and metallic material we stand on, the iron in our blood, the calcium in our teeth, the carbon in our genes were produced billions of years ago in the interior of a red giant star. We are made of star-stuff.
— The Cosmic Connection: An Extraterrestrial Perspective, Carl Sagan, 1973
Although Sagan was not the first one to point this out nor to use the now-famous expression, he was largely the one to popularize it as he continued using it in articles and presentations, and particularly in the excellent 1980 PBS television series Cosmos: A Personal Voyage.
So that’s my final thought for the season: we are born from the collapsed heart of ancient stars. If that is not awe-inspiring, I don’t know what is.
Note: The image above is not a photograph of any real star formation in our night sky, it’s a digital painting I made for the love of it. I hope the picture comes out properly, I understand that a previous version came out way too dark on some computer monitors. I tinkered with it, and I hope it is fixed now.
Image by Sophie Lagacé 2010-2013, licensed under CC BY-NC-SA 3.0.