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Episode 4: Mushroom Rings, Apple Cider, Tree Sap, Glass Colors, Lost Connections

Hello young scientists. I’m Dr. Universe and if you’re anything like me, you’ve got lots of big questions about our world. On this episode, we’ll investigate questions about why mushrooms grow in rings, how to make apple cider, the art of stained glass, why trees have sap and finally investigate why the internet goes down. Listen now or find other episodes on:

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The Latest Questions and Answers

  • Why do some cheeses stink?

    When you take a whiff of stinky cheese, that smell is coming from one of its very important ingredients: microorganisms.

    Microorganisms are so small, you’d need a microscope to see them, but sometimes they give off a big stink. To find out more about stinky cheese, I talked to my friend Minto Michael.

    Michael is a professor of dairy science at Washington State University and told me microorganisms do a few different jobs to help make cheese.

    Read Story
  • Why does frost make shapes like flowers and ferns?

    Dear Grace,

    You’re right: frost can sometimes form patterns that look like the ferns or flowers we find in nature.

    Those frosty shapes we see on the surface of windows start out as water in the air, said my friend Kai Carter. Carter is a meteorologist with Washington State University’s AgWeatherNet team.

    Kai Carter, Field Meteorologist

    If you’ve ever had a glass of ice water, you may have noticed droplets formed on the outside of the glass. The droplets actually came from water in the air. This water condensed from the air onto the surface of your cup, which means it turned from a gas to a liquid.

    Read Story
  • Can a shadow make a shadow?

    Dear Aven,

    When we look around our world, we can find all kinds of shadows. One way we can explore the answer to your shadow question is with a little experiment.

    My friend Anya Rasmussen, a physics professor at Washington State University, told me all about it.

    First, you will need to cast your shadow on a wall. Rasmussen reminded me shadows form when an object—such as your body— blocks light and keeps the rays from reaching a surface—like a wall.

    Read Story
  • Why do we have seasons?

    Dear Bella,

    It turns out seasons can be quite different depending on where you live. But no matter where you live, the reason for the seasons has to do with the way the Earth rotates.

    To find out exactly why we have seasons, I talked to my friend Vivienne Baldassare, a physics and astronomy professor at Washington State University.

    Read Story
  • Why does water in ponds not get soaked up by the dirt at the bottom?

    That’s a great observation. If we investigated the bottom of a pond, we might find a few different things.

    Read Story
  • Dr. Universe, a grey cat with a lab coat, looking through binoculars How many black holes are in the universe?

    Dear Krisha,

    While we can’t see black holes with our eyes, astronomers have figured out how to spot these objects in our universe.

    One astronomer who is really curious about understanding black holes is my friend Sukanta Bose, a researcher at Washington State University.

    First, he told me there are different kinds of black holes. Supermassive black holes can be millions to billions of times the mass of the Sun. We have a supermassive black hole in our own Milky Way galaxy called Sagittarius A*, which is pronounced as Sagittarius A-star.

    Read Story
  • Illustration of smiling apples Why do trees have sap?

    Just as blood moves important stuff around the human body, sugary sap moves important things around a tree.

    My friend Nadia Valverdi told me all about it. She’s a researcher at Washington State University who studies how apple and cherry trees survive in different environments.

    When we eat food, like a delicious apple or a handful of cherries, we get important nutrients.

    Read Story
  • How does stained glass get its colors?

    Dear Emily,

    Ever since humans discovered they could use sand to make glass, they’ve been experimenting with it. They even learned how to control the colors.

    My friend Dustin Regul is a stained glass artist and painter who teaches fine arts at Washington State University. He told me more about where glass gets its color.

    “It’s actually metals that help change the color of the glass,” he said.

    Read Story
  • Why does the internet go down?

    The internet has helped many people connect with classmates, friends and family during the pandemic. But you’re right, sometimes the connection gets lost.

    My friend Dingwen Tao, an assistant professor of computer science at Washington State University, said we can think about the internet like a highway of information.

    You may remember from our question about how the internet works that information, like the data that makes up your favorite cat video or science website, travels through electronic signals we cannot see with our eyes.

    Read Story
  • How do you make cider?

    We can make cider with juice from apples. There are many different kinds of apples and a few different ways to squeeze out the juice.

    My friend Bri Valliere told me all about it. She’s a food scientist at Washington State University who knows a lot about cider.

    The first step is to pick out the apples. Honeycrisp apples will make a sweet cider. Granny Smiths are more acidic and will make a tart cider.

    “We could make a single batch of one kind, or we could mix different kinds of apples together and see how it turns out,” she said. “No matter what, it’s going to taste good.”

    Read Story


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