Pluto is tiny, icy, and used to be the ninth planet in the solar system. Used to be. So why isn’t Pluto a planet anymore?
Join Molly and co-host Momo as they learn Pluto’s history, talk to planetary scientist Kelsi Singer about NASA’s New Horizons mission, and even hear from the planet itself. All that plus a nifty new mystery sound!
This episode was sponsored by:
Indeed (Indeed.com/BRAINS) - Claim your $75 sponsored job credit to upgrade your job post. Terms and conditions apply.
Factor (Factormeals.com/brainson50) to get 50% off.
IXL (IXL.COM/FIELDTRIP) to get a 20% off an IXL membership.

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Why isn’t Pluto a planet anymore?

Brains On!® is a science podcast for curious kids and adults from American Public Media. Each week, a different kid co-host joins Molly Bloom to find answers to fascinating questions about the world sent in by listeners. Like, do dogs know they’re dogs? Or, why do feet stink? Plus, we have mystery sounds for you to guess, songs for you to dance to, and lots of facts -- all checked by experts.

Kids & Family

Education for Kids

Looks like Marc has a beautiful new plant but doesn’t know where to put it. Direct sunlight or indirect sunlight? It’s too hard to figure out! But you know what’s not hard to figure out? Whether or not you should play Molly’s new game, Radical Design! Grab your Smarty Pass to see what producers Marc Sanchez and Rosie duPont think homes would look like on other planets!

Smarty Pass Sneak Peek: Radical Design

Humans have visited the Moon but we’ve never lived there. Could we build a home on our lunar neighbor? Join Molly and co-host Ira as they find out why the Moon can be a dangerous place, and what it would take to live there. We’ll imagine a visit to a lunar hotel, hear about all the stuff humans have left up there and even hear a song sung by the Moon herself!
Featured Expert: Phil Plait, astronomer, journalist and author of several books, including, Under Alien Skies: A Sightseer’s Guide to the Universe, which uses science and imagination to paint a picture of what it would be like to vacation on the moon.
Subscribe to Smarty Pass for ad-free feeds, bonus episodes, and ticket discounts!
Today’s episode is sponsored by:
- Poshpeanut.com/brainson - Receive 20% off your first order
- Indeed.com/brainson - Receive a $75 sponsored job credit with code brainson 
- Paramount’s IF - From writer and director John Krasinski comes a new film about what happens to our Imaginary Friends (IFs) when we grow up. Out in theaters on May 17th!

How to build a house on the Moon

Looking for an escape? Join Molly and co-host Julian as they explore Antarctica! They’ll learn about Antarctica’s massive ice sheets and active volcanoes — plus they’ll meet the largest land animal on the continent! (Hint: it’s black, shiny, and can perch on a pencil eraser!) 

Then they’ll chat with scientist Dr. Jennifer Mercer about what it’s like to live and work in one the coldest places on the planet and explore what Antarctica was like 90 million years ago. (Hint: It was a lot like a beach resort!) And stick around for a  mystery sound that’s so cool it’ll give you goosebumps!
Subscribe to Smarty Pass for ad-free feeds, bonus episodes, and ticket discounts!
Today’s episode is sponsored by:
- Sitkaseafoodmarket.com - Use promo code Molly35 to receive $35 off your first order.
- Indeed.com/brainson - Receive a $75 sponsored job credit with code brainson
- Poshpeanut.com/brainson - Receive 20% off your first order

Are there insects in Antarctica?

Have you ever taken a big ol’ whiff of rotten milk? It probably smelled like dirty socks or stinky garbage. Blech! But why does food go bad, and how can we be sure that something is fresh and safe to eat?
Join Molly and co-host Rachel as they explore the world of food expiration dates — those little numbers and dates on food packages that help us figure out how old food is! Together, they’ll find out why food goes bad, listen to a rotten egg sing about the power of the sniff test, and learn about the history of expiration dates from Forever Ago host Joy Dolo! All that plus a treat for your ears — an all-new mystery sound!
Subscribe to Smarty Pass for ad-free feeds, bonus episodes, and ticket discounts!
Today’s episode is sponsored by:
- Sitkaseafoodmarket.com - Use promo code Molly35 to receive $35 off your first order.
- Indeed.com/brainson - Receive a $75 sponsored job credit with code brainson
- Poshpeanut.com/brainson - Receive 20% off your first order

How can you tell when food is expired?

Ouch! If you’ve ever stubbed your toe, gotten a paper cut or fallen off your bike, you know that getting hurt is no fun. Sometimes we can take medicine to help feel better, like ibuprofen. But how does that medicine know where to go in our bodies to stop the pain? 

In this episode, Molly and kid co-host Skylar explore where pain comes from and chat with expert Dr. Amanda C de C Williams about why it’s useful. Then they’ll eavesdrop on an ibuprofen pill on its first day of work to find out how it does its job. And of course, an all new mystery sound!
Subscribe to Smarty Pass for ad-free feeds, bonus episodes, and ticket discounts!
Today’s episode is sponsored by:
- Sitkaseafoodmarket.com - Use promo code Molly35 to receive $35 off your first order.
- Indeed.com/brainson - Receive a $75 sponsored job credit with code brainson

Why isn’t Pluto a planet anymore?

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