Welcome back, 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 explore questions about flying squirrels, our curious pets, frost, and stinky cheese. Listen now or find other episodes on:
Why do mirrors fog up when you breathe on them?
That’s a great observation. When you breathe out, you let a couple of different things into the air.
Not only do you breathe out carbon dioxide, but you also breathe out teeny tiny droplets of water. These water droplets are so small we can’t see them with our eyes.Read Story
How do birds know where to migrate?
There are all kinds of different birds on our planet, and they migrate to different places.
My friend Heather Watts, a researcher at Washington State University, is really curious about bird migration and told me more about how birds know where to go.Read Story
Why does oil on the street look like a rainbow?
When it rains, sometimes we can see oil on the street rise to the top of puddles and spread out into a rainbow of colors.
One of the main reasons we see color is because of light, said my friend Cigdem Capan, a physics instructor at Washington State University.
She reminded me that when our eyes sense colors, we can trace those colors back to different wavelengths of light. Perhaps you can make some waves in the air with your hand. Make small, tight waves. Now make a big, wide waves.Read Story
How can you tell if a fish is female or male? Or if it is a kid or adult or teenager?
There are more than 34,000 species of fish on our planet. It can be tricky to tell the age or sex of a fish, but biologists have come up with a few different ways to find out.
My friend Paul Wheeler, a fish biologist at Washington State University, told me all about it.Read Story
Do flying squirrels really fly?
Flying squirrels may not really fly, but they do have flaps of skin on their bodies that act like parachutes and help them glide through the air.
My friend Todd Wilson told me all about it. He’s a wildlife biologist with the U.S. Forest Service in Oregon and graduate of Washington State University who researches Pacific Northwest ecosystems and the animals that call them home— including flying squirrels.Read Story
Why do cats and dogs spin around before they sit?
That’s a great observation about cats and dogs. Even I wasn’t sure why cats spin around before they sit down, so I took your question to my friend Dr. Jessica Bell.
She is a veterinarian at the Washington State University Veterinary Teaching Hospital and has seen quite a few cats and dogs walk in a little circle before they sit down.
“It’s a common thing we observe as veterinarians, but we can’t talk to cats and dogs and ask them ‘why,’” she said. “From a behavioral standpoint, it probably stems back to their wild instinct.”Read Story
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?
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?
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?
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
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