How old is the oldest slice of Earth's seafloor? The answer is more contentious than you would think. Today, we visit one of the most debated locations in the show: a small island off the Greenland shore named Akilia. Everything about these rocks has been contested, and we'll meet three scientists who form cornerstones of the debates.

Extra Credit: Watch something on an old CRT TV, or count tree rings in a stump.

Earth’s crust is shattered into dozens of moving plates, but many other worlds operate very differently. What are some alternatives to plate tectonics?

Today, we’ll compare tectonics on Earth with tectonics on other planets, through the lens of 3.9 billion-year-old rocks from Greenland. On the way, we’ll visit the westernmost town in the USA, visit one of our cosmic neighbors, and learn about the Occam’s Razor of geology.

Extra Credit: find today’s planet in the night sky, drop a pebble every day this week and see if anything changes, or read “The Long Rain” by Ray Bradbury.

Donate to support the show- anything is appreciated!

Click here for the audience survey!

Click here to read Dylan's Nature paper!

This season's final arc is set in Greenland. Let's start with the most common rocks in the region: what are they and what stories do they tell about the world 3.9 billion years ago?

Along the way, we'll weave a tapestry of stone, boil some rocks, and learn a bit about Dylan's birthstone.

Extra credit: try the Play-Doh experiment from this episode, or make some stone soup.

Click here for the audience survey!

Donate to support the show- anything is appreciated!