How did water arrive on planet Earth?

Today, we learn just how much water Earth has (spoiler: probably not as much as you'd think), and where it came from in the first place. We'll take a joyride around the early solar system, learn how our stellar neighborhood is like a snow-capped mountain, and discover how the planet Jupiter might have played a crucial role in creating the oceans of Earth.

Extra credit: Drink some water, make a snowball, or watch the Kevin Costner classic Waterworld.

How do we know when the first oceans existed?

Water leaves its' fingerprints over every surface of Earth, even in the oldest, toughest crystals. Today, we'll take an imaginary ride through the earliest oceans, examine how water slowly transforms everything it touches, and how these changes are recorded in the Jack Hills zircons, 4.4 billion years ago.

Extra Credit: Make an underwater rock garden, walk into a muddy beach, or visit a dog park.

How and where did the first cells form on planet Earth, 4 billion years ago?

To answer that question, we investigate why oil and water hate each other, explore the seafloor with the Titanic's discoverer, and take a relaxing dip inside a hot spring.

Extra credit: drop some olive oil into water, or make a trip to the closest hot spring in your local area.

Season 1 Finale.

What was the first living thing on Earth, when did it live, and what did it do?

Today, we end Season 1 by meeting LUCA, the oldest ancestor for every living thing on Earth today. On the way, we'll tackle how complex life formed in a chaotic universe and why it hasn't formed again, take a trip down life's family tree, and meet a deadly modern microbe- one of the closest relatives of the oldest living thing.

Thank you all for listening to Season 1, and stay tuned for Season 2!

Extra Credit: Take a look at family photos, or check your canned foods for botulism.