The invisible substance that structures our universe

Dark matter is invisible. It's all around us. And we have no idea what it is.

The universe is so much bigger than what people can see. Visible matter — which makes up the things you can see like the ground, the Sun, the screen you're reading this on — makes up only about 4 or 5 percent of the known universe. Scientists like Priyamvada Natarajan, an astrophysicist at Yale University, say that dark matter is the bulk of the matter that exists. But because it doesn't interact with light, we have very few ways to directly examine it.

In this episode, we talk to Priya about how scientists first discovered dark matter, why we care about studying it and what it can tell us about the universe we live in.

This episode is part of Short Wave's space camp series about all the weird, wonderful things happening in the universe. Check out the full series.

Questions about the state of our universe or smaller happenings here on planet Earth? Email us at shortwave@npr.org — we'd love to consider it for a future episode!

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This episode was produced by Hannah Chinn. It was edited by Rebecca Ramirez. Regina G. Barber checked the facts. The audio engineer was Gilly Moon.

Special thanks to our friends at the U.S. Space & Rocket Center, Home of Space Camp®.