An Orbital Path episode all about...an orbital path! Planet 9's, to be exact. The replacement for Pluto as our solar system's ninth planet is out there somewhere, and astronomers can see the ripples it creates, especially at this time of year.

In Search of Planet 9

Astronomer Michelle Thaller takes a look at the big questions of the cosmos and what the answers can reveal about life here on Earth. From podcast powerhouse PRX, with support from the Sloan Foundation.

Natural Sciences

Science & Medicine

Science

Orbital Path signs off with a site visit to NASA’s mysterious and extraordinary building 29.

Building 29

Billion-year-old asteroid dust, coming right up!

Hello, Asteroid!

Astronomers investigate a mystery that is 13 billion years old.

Black Holes from the Dawn of Light

NASA develops a futuristic space laser. Launches it into orbit. And aims it directly back at planet Earth.

Space Lasers for the Home Planet

Humans! Time to get over your three-dimensional selves.  Brian Greene — world renowned physicist, bestselling author, NOVA host, and serial Colbert guest — explains why.

In Search of Planet 9

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