Yesterday Facebook decided to remind me that sixteen years ago I posted a pie chart with the caption, “Anytime I think about this my mind is blown.” I hadn’t thought about that post in years, but the moment I saw it again I laughed because my reaction was exactly the same. It still blows my mind. Not because the science has been overturned, but because after another sixteen years of extraordinary discoveries, we still understand only about five percent of what appears to exist.
Sixteen years later, the percentages have shifted only slightly. We now estimate that ordinary matter makes up about 5% of the universe, dark matter around 27%, and dark energy about 68%. In other words, despite another decade and a half of billion-dollar telescopes, satellites, particle detectors, and some of the brightest minds on Earth working the problem, we still only understand about five percent of what appears to exist.
That’s one of those facts I think many people simply never hear.
If you ask someone what the universe is made of, most would probably answer, “Stars, planets, galaxies, black holes...” Those are certainly spectacular, but together they amount to little more than cosmic garnish. Every mountain you’ve climbed, every sunset you’ve watched, every dinosaur that ever roamed the Earth, every Beatles record, every cup of coffee you’ve spilled on your keyboard, every person you’ve ever loved—all of it exists inside that tiny five-percent slice.
The rest?
Something else.
We call it dark matter not because it’s black, but because we don’t know what it is. We call it dark energy not because it resembles energy as we normally think about it, but because we needed a name for whatever seems to be causing the expansion of the universe to accelerate. They’re less explanations than they are admissions. Labels we’ve attached to mysteries because “we have absolutely no idea” doesn’t fit very neatly into a scientific paper.
In fact, some of the newest observations have scientists wondering whether our understanding of dark energy itself may need revision. Not because we’ve solved the mystery, but because the mystery appears to be even stranger than we imagined. I find that oddly comforting.
We live in an age where people confidently argue about everything from politics to nutrition to the correct way to load a dishwasher, yet the universe occasionally clears its throat and reminds us that we’re still scratching our heads over ninety-five percent of reality. There is something profoundly humbling about that. Not discouraging. Humbling.
The older I get, the more I find myself valuing that feeling. The more I learn, the less interested I become in pretending certainty where none exists. Science isn’t beautiful because it has all the answers. It’s beautiful because it has the courage to say, “This is everything we’ve discovered... and here’s the enormous pile of things we still don’t understand.”
That little pie chart blew my mind sixteen years ago.
Oddly enough, it blows my mind even more today.