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Ask Dr. Universe rcwebber

Dr. Universe: What are butterfly wings made of? Serenity, 12

Dear Serenity,

Butterfly wings may be quite thin, but they are also durable and strong. This strength comes from the material that makes up the wings: chitin (KITE-IN).

Chitin is a kind of building material we find in nature. Chitin makes up not only the wings of butterflies but also the outer skeletons—or exoskeletons—of crabs, shrimp and lots of other insects.

My friend David James, an entomologist at Washington State University, told me all about it.

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Dear Dr. Universe: Why do we get hiccups? – William, 9, Indiana

Dear William,

When you get hiccups, it might seem like they are coming out of nowhere—and before you know it, they’re gone.

To find out exactly why hiccups happen, I talked to my friend Dr. Luisita Francis, a professor of medicine at Washington State University.

She told me part of the reason humans get hiccups has to do with a very important muscle in the abdomen: the diaphragm (DYE-UH-FRAM).

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Dr. Universe: How is DNA built? - Riot, 8, Everett, WA

Dear Riot,

Pretty much every living thing on our planet—from a blue whale to a tiny ant—has something in common. We all have cells, which are the building blocks of life, and inside of those cells we have DNA.

My friend Gunjan Gakhar, a Teaching Assistant Professor at Washington State University, was happy to help with your question.

First, she reminded me that DNA contains the instructions for living things to grow, survive, and reproduce. DNA determines everything from our eye color to our hair color to our height.

“DNA is built like a ladder,” she said. “And if you twist that ladder, that’s … » More …

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Dr. Universe: Why do numbers never end? – Louis, 11, Wenatchee

Dear Louis,

That’s a great observation about numbers. Whether you start counting backwards or forwards, numbers never seem to end.

To find out more about these mysterious numbers, I took your question to my friend Kevin Fiedler. He’s an assistant professor of mathematics at Washington State University.

He reminded me that there are a lot of different rules mathematicians follow. For instance, if you think of a number, you could always add one to it.

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Dr. Universe: Why do people have feelings like boredom, happiness, sadness and love? - Sophia, 11, Utah

Dear Sophia,

You’re stuck inside on a rainy day when all of a sudden you start to feel a bit bored. Maybe you aren’t sure what to do with the feeling. Maybe you decide to read a book or bake some cookies and the feeling starts to fade.

Perhaps you then start feeling happiness from doing an activity you love. You know, pretty much everyone experiences a variety of different feelings every day.

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Dr. Universe: What did praying mantises evolve from? – Tara, 12

Dear Tara,

When you think of the Jurassic Period, you might think of dinosaurs, but all kinds of insects, including praying mantises, roamed the Earth back then, too.

Some of the mantises died and fossilized into rock and amber, which helped to preserve them for hundreds of millions of years. As scientists uncover these fossils in modern times, they can learn more about the life histories of insects.

That’s what I found out from my friend Elizabeth Murray, an entomologist at Washington State University, who is very curious about the diversity of insects on our planet.

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Dr. Universe: How come some people can’t see color? – Pearl, 8, South Dakota

Dear Pearl,

Our brains have the amazing ability to gather information and interpret it. This ability to gather and interpret—or perceive— is a big part of what helps humans see colors.

Our eyes have tiny cones that receive light, turn it into chemical energy and activate nerves that can send information to the brain. You might see an apple and think to yourself, “That’s the color red.”

My friend Rachna Narula, an optometrist at Washington State University, told me all about it.

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Dr. Universe: Why is too much salt bad for you? - Dot, 12, Palm Desert, CA

Dear Dot,

The human body uses salt in all kinds of different ways. Salt helps the cells in our bodies do their jobs, it helps the muscles contract and it plays a big part in keeping us hydrated.

But as you’ve pointed out, too much salt can cause problems. My friend Catalina Aragon told me all about it. As an assistant professor at Washington State University Extension, she works with communities all across the state to share information about food and how it impacts our health.

When humans eat food, they can get lots of nutrients such as calcium, potassium, iron and sodium. Sodium is … » More …

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Dr. Universe: How do germs enter the body? -Amari, 8, Indiana  

Dear Amari, 

There are many different ways germs can enter the body. Sometimes they find a way in through an opening like the mouth, nose, eyes or a cut in the skin.   

Most of these germs—what scientists call viruses and bacteria—are so small we’d need a microscope to see them.

My friend Leigh Knodler is a researcher at Washington State University who works with a particular kind of bacteria called Salmonella.  

Salmonella can sometimes live on food, such as undercooked chicken or unwashed fruits and vegetables. It typically enters the body through the mouth when someone takes a bite of food.  

If we followed Salmonella through the body, it would pass through the esophagus, the stomach and finally into the intestines.

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Dr. Universe: Why do people like listening to music? – Bruce, 10, Tacoma, Wash.

Dear Bruce,

Think of your favorite song. Maybe it brings you happiness or joy. Maybe it makes you want to start dancing. Or maybe it’s a sad, melancholy song, but you still really like it.

From the radio to concerts to our mobile devices, music is all around us. To find out exactly why people like listening to music, I talked to my friend Sophia Tegart.

Tegart is a flutist, musicologist and assistant professor at Washington State University. She said one of the reasons many people like listening to music is because it can affect emotions.

“Music is emotion you can hear,” she said.

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Dr. Universe: How does hail form? -Emilio, 11, San Diego, California

Dear Emilio,

During a thunderstorm, there are often lots of tiny water droplets in the clouds that form precipitation like water, snow or hail. But that precipitation doesn’t always fall right to the ground.

Sometimes a falling raindrop will get swept back up in a current of air. The air current can carry the raindrop to higher parts of the thunderstorm cloud where temperatures are below freezing.

Under these super cold temperatures, a raindrop will freeze. Then, other water droplets will start clinging to the frozen droplet. This is how hail, or a hailstone, begins to form.

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Dr. Universe: Why do things like rockets catch fire as they pass through Earth's atmosphere? - Conner, 11, Dunn, North Carolina

Dear Conner,

When objects like spacecraft pass through Earth’s atmosphere, things can really heat up.

To investigate the answer to your question, I talked to my friend Von Walden. He’s a professor and researcher with Washington State University’s Laboratory for Atmospheric Research.

First, he said it helps to know a bit about the differences between Earth’s atmosphere and space.

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Dr. Universe: How are baseballs made? -Kaden, 11, Saratoga Springs, Utah

Dear Kaden,

There are a lot of steps that go into making a baseball. As we investigate this question, we’ll focus on the ones made for Major League Baseball.

My friend Lloyd Smith, a mechanical engineer and director of the Sports Science Laboratory at Washington State University, told me all about it.

A while back, he had a chance to visit a facility in Costa Rica where they make MLB baseballs. Smith said it begins with a small sphere called a pill, which has a cork center and a couple of rubber layers.

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Dear Dr. Universe: How does COVID-19 affect our household pets? – Kolton, 11, Michigan

Dear Kolton,

A lot of researchers around the world are investigating this very question. While we don’t know everything about how the SARS-CoV-2 virus affects household pets, there are some things we do know.

My friend Dr. Raelynn Farnsworth, a veterinarian at Washington State University, told me all about it.

The risk of household pets spreading the SARS-CoV-2 virus to humans currently seems to be very low, she said. But a human who has the virus could potentially spread it to an animal, like a cat or dog, if they’ve been in close contact.

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Dear Dr. Universe: How did you get your name? -Byron, 13, Pennsylvania

It turns out a lot of kids around the world have been wondering about the answer to this very question—after all, you don’t hear the name “Dr. Universe” every day. Believe it or not, I wasn’t entirely sure about the origin of my name. But my friends at the Washington State University Libraries had the answer in their historical archives. Yes, the local library is a great place to visit when you have a big question. As I read through the archives, I learned that I wouldn’t have my name if it weren’t for two people who worked at the university. Read More ...

Dr. Universe: Why does the sky turn darker in winter? - Alex, 6, Cincinnati

Dear Alex,

As winter gets underway here in North America, you may notice we don’t feel the sun’s rays for quite as many hours as we did in fall and summer.

To find out why this happens, I talked with my friend Vivienne Baldassare, an astronomer at Washington State University.

She said the reason we get fewer hours of daylight in the winter has to do with how Earth rotates. As our planet goes around the sun, it is always rotating. This rotation is also why we have day and night.

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Why do bacteria in the Yellowstone hot springs make the water different colors? -Ava, 9, Kennewick, WA

Dear Ava,

One of the most eye-catching hot springs in Yellowstone National Park is the bright and colorful Grand Prismatic Spring. It’s blue in the middle with bands of colors ranging from green and yellow to orange and reddish-brown.

My friend Peter Larson is a geologist at Washington State University who is very curious about hot springs. He spent much of his research career in Yellowstone National Park.

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Dr. Universe: What bacteria make us get stomach bugs? – Austin, 9, Texas 

Dear Austin,

There are all kinds of tiny pathogens, including bacteria and viruses, in our world. Some of them are helpful and do things like keep the human gut healthy—but there are others that can make us quite sick.

I talked to my friend Alan Goodman about it. He’s an associate professor at Washington State University who knows a lot about the pathogens that can cause illness in people and other animals.

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Dr. Universe: Why do animals have different hearing? – Dorothy, 9, Washington State

Dear Dorothy,

You’re right—different animals can hear different types of sounds. To find out more about it, I talked to my friend Dr. Vishal Murthy, a veterinarian at Washington State University.

Murthy reminded me sound comes from vibrations that travel through the air. For instance, when you feed your pet, the kibbles that fall into the bowl send out vibrations to your pet’s ears.

Some animals, like cats, dogs, elephants and humans, have ears that stick out and can help funnel these vibrations into the inner ear.

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Dr. Universe: How did the sun form? - Krystal, 7, Seattle, Washington State

Dear Krystal,

Our sun may be one of the billions of stars in the galaxy, but it’s the only star right here in our solar system. It keeps us warm and gives us light, which is important for all kinds of living things on our planet.

To find out more about how stars like our sun form, I talked to my friend Jose Vazquez, an astronomer at Washington State University.

He reminded me that when we talk about the size of stars, we often talk about their mass. You can think of mass as the amount of “stuff” or matter that makes up an … » More …

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Dr. Universe: What’s the purpose of baking soda? What’s the purpose of baking powder? What’s the difference between the two? - Kyle, 9, Florida

When I got your question, I headed straight to my kitchen cabinet. I grabbed some baking soda and baking powder from the shelf and made some observations. Not only did the baking soda and baking powder look similar to one another but both contained an ingredient called sodium bicarbonate. Read More ...

Dr. Universe: What are the strings inside a pumpkin? Some are attached to the seeds. – Maggie, Woodinville, WA

Dear Maggie,

If you open up a pumpkin, you would see all kinds of different things inside. Some people call all this gooey stuff the pumpkin’s “brains” or its “guts.”

There’s the meaty orange flesh, sticky pulp, lots of seeds, and, of course, all those little strings. The strings actually have a really big job.

My friend Lydia Tymon is a plant pathologist. That means she is like a doctor for plants—and she was happy to hear about your question.

The pumpkin’s strings, or fibrous strands, help the seeds get something important while the pumpkin is growing on the vine: nutrients.

You might think … » More …

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Hey Dr. Universe! We have a question...Why can't we breathe in space? Thanks! From, Mrs. Barnes's Fifth Grade Class!

On Earth, humans have oxygen to breathe. But there’s very little oxygen to breathe in space. Space is actually a kind of vacuum, which means there isn’t a whole lot of matter, or stuff, out there between the planets and the stars. For Earthlings like you and me, oxygen is an essential part of life. While 21% of Earth’s atmosphere is oxygen, my friend Yimo Liu reminded me it wasn’t always that way. Read More ...

Dr. Universe: Why does sleep feel so short? - Brooklyn, 12

That’s a great observation. When my friend Ashley Ingiosi was a kid, she remembers how napping in the car during a four-hour drive to her grandparents’ house seemed to make the time fly by. Maybe you’ve had a similar experience. As a researcher at Washington State University, Ingiosi is really curious about what goes on within the human brain during sleep. She was happy to help with your question. Read More ...

Dr. Universe: How do human hearts beat? -Jacob, 12, Forney, Texas

Dear Jacob,

You have a heart that beats every single day—even when you aren’t thinking about it. It likely beats about 60 to 100 times per minute. That adds up to more than a billion beats in a lifetime.

To find out how exactly how it all works, I talked to my friend Garry Smith, a researcher at Washington State University.

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Dr. Universe: What are cells made of? – Lela, 10, Bogart, GA

Dear Lela, You have all kinds of cells in your body that do lots of different things. In fact, there are about 200 different types of cells in the human body—from blood cells to skin cells to bone cells. To find out exactly what all those cells are made of, I visited my friend Deirdre Fahy. Fahy is a scientist at Washington State University who is curious about how and why things work, including our cells. She reminded me the human body is made up of billions of cells. You might think about each cell as if it were a tiny room. But this room, or cell, is so small, you’d likely need a microscope to see it. Read More ...

Dr. Universe: How do memory cards work? - Ngyuen, 10, Vietnam

Memory cards can help us store all kinds of information—from pictures to songs to videos. While some of the early computers were as big as two refrigerators, they had only enough memory to store what would today be a single photo. Now, we can store thousands of photos on a memory card the size of a fingernail. Read More ...

Dr. Universe: When would a clam open its shell? Why do the shells open? As far as I know, it opens when boiled for food. - Teng, 5, China

Dear Teng, There are a lot of different reasons why a clam might open its shell. My friend Jonathan Robinson, a marine ecologist at Washington State University, told me all about it. If we spent some time where the ocean meets the shore, or the intertidal zone, we might observe how clams open their shells when they need to eat, breathe or move around. Read More ...

Dr. Universe: How do we clone things? – Raphael, 8, São Paulo, Brazil

From frogs to sheep to cats, humans have learned to clone all kinds of organisms. Like you, I was curious how it all works, so I talked to my friend Jon Oatley, a researcher at Washington State University. First, he told me that mammals—like you and me—are made up of billions of building blocks called cells. Other organisms, like amoebas, are just a single cell. Inside each cell is a nucleus, which is like a small envelope that protects something very important: DNA. Read More ...

Dr. Universe: How do lungs work to help keep you alive? – Ellie, 11, North Carolina

Dear Ellie,

Take a deep breath. As air travels through your nose and mouth into your lungs, it brings oxygen into the body. To find out exactly how it all works, I talked to my friend Kim Chiok, a researcher at Washington State University.

In the lab at WSU, she designs experiments to help us learn about diseases that impact the lungs and other parts of the body that help us breathe.

When you breathe in, little hairs in your nose help filter out particles like dust, so they don’t enter the body. The air warms up as it flows into a tube-like structure … » More …

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Dr. Universe: Why do we have to keep things like ice cream and popsicles in the freezer? -Asia, age 9, Seattle, WA

Dear Asia,

You may have noticed ice cream and popsicles will melt when they are out of the freezer for too long. To find out exactly why this happens, I headed to the Washington State University Creamery.

My friend John Haugen, the creamery manager, was happy to help with your question. He said a big part of the answer has to do with something called matter. All things in our universe are made up of matter—even ice cream and popsicles.

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Dr. Universe: How do mountains form? -Zane, age 8

Dear Zane,

When you walk around on land, you are walking on top of Earth’s rocky crust. Below the crust is another thick layer of rock. These layers form Earth’s tectonic plates and when those plates collide with each other, they often form mountains.

[caption id="attachment_6257" align="alignright" width="198"] Julie Menard[/caption]

To find out more about how mountains form, I visited my friend Julie Menard, a professor at Washington State University who is very curious about geology.

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Dr. Universe: Why do we have to blink? - Michael and Virgil, 3 and 5, in Sioux Falls, SD

Dear Michael and Virgil, If you’ve ever had a staring contest with a friend, you may have felt your eyes start to get tired and dry. Eventually, you just had to blink. Blinking helps our eyes stay healthy, and my friend Dr. Karen Janout, a clinical assistant professor at Washington State University, told me all about it. She said that with each blink, your eyelids help spread tears over the surface of your eyes—and you actually do this a lot. Humans blink an average of 15 to 20 times a minute, which adds up to somewhere around 5.2 to 7.1 million blinks a year. Read More ...

Dr. Universe: How do tiny seeds make huge trees? – Robin, age 8

Dear Robin, If you’ve ever eaten a handful of trail mix, you’ve likely eaten quite a few seeds from trees. Some nuts, like cashews and almonds, are also seeds that can give us energy when we hike or play. Seeds actually store up their own energy in the form of something called starch, which is kind of like the food a seed needs to survive. The seed will use this stored up energy to start growing into a tree. Read More ...

Dr. Universe: Why does it make noise when you snap your fingers? – Amelia, Michigan, 12

When I got your question, I snapped my fingers a few times to try and find the exact source of the sound. After a few tries, I decided to ask my friend Troy Bennefield, the director of Athletic Bands at Washington State University. While we may start a snap with the top of our thumb and middle finger touching, he said that the snapping sound actually happens when the middle finger hits the palm area at the base of the thumb. Read More ...

Dr. Universe: Why are some berries poisonous? Where does the poison come from and how does it get in the berries? - Bianca, 4 1/2, California  

A lot of living things on our planet have defenses they use in the wild to help them survive. For some plants, being poisonous may help keep them from becoming someone’s dinner. Wendy Hoashi-Erhardt That’s what I found out from my friend Wendy Hoashi-Erhardt, a scientist who directs the Small Fruit Plant Breeding program at Washington State University. Read More ...

Dr. Universe: Why do trees grow so slow? – Ana, 7, Covert, MI

When you eat food, you get a lot of important nutrients that help you grow. The trees that live on our planet also need some nutrients to grow. Trees use their leaves to help capture energy from the sun to make their own food. But as you may have noticed, a lot of trees lose their leaves during certain times of the year. Without leaves, they can’t make nearly as much food, and without those important nutrients, they can’t grow very fast. That’s what I found out from my friend Tim Kohlhauff, a certified arborist and urban horticulture coordinator at Washington State University. He is very curious about the lives of trees. Read More ...

Dr. Universe: How do worms help protect the dirt? -Fisher, 7, Palouse, WA

Dear Fisher,

Worms can help the soil in a few different ways. One helpful thing worms do is move around different materials, such as leaves and grasses, and make holes in the soil. That’s what I found out from my friend Lynne Carpenter-Boggs, a soil scientist at Washington State University, who was happy to help with your question. Lynne Carpenter-Boggs “Worms are actually very strong,” Carpenter-Boggs said. “They can break through soil and make holes that allow air, water and plant roots to follow those channels.” Read More ...

Dr. Universe: How do fish migrate and why? – Norma, 10, Indiana

While a lot of fish swim from one region to another to find food or have babies, different fish species migrate in different ways. That’s what I found out from friend Steve Katz, a professor at Washington State University who knows a lot about our planet’s natural resources and has researched fish such as steelhead trout, tuna and seven-gilled sharks in the Pacific Northwest. He said that steelhead trout often navigate through the water with help from a sense of smell. Steelhead trout use their nostrils to pick up on chemicals from rocks that have dissolved in the water. The differences in the scents of the water help them know which river or stream to follow. Read More ...

Why are people most commonly right-handed? Who/what deicides if we are left-handed or right-handed? Are you left-handed or right-handed? Mya, 8, Alexandria, VA

We don’t know exactly why so many people are right-handed, but one place we might look for answers is in the material that makes a person who they are: genes. The genes in your body help control all sorts of things from the color of your hair to your skin to your eyes. These traits can be passed down through generations—from grandparents to parents to you. My friend John Hinz, who is a right-handed professor at Washington State University, knows a lot about genes and the study of how organisms pass their genes through generations. Read More ...

Dear Dr. Universe: How did people figure out how much a whole planet weighs? They could not have just put it on a scale! How did they do it? – Angel, 14, California

About 300 years ago during another pandemic, there was a person named Sir Isaac Newton who spent a lot of time at home thinking about the universe. He was thinking about how objects fall and started to wonder if the same force that made objects fall also kept the moon in its orbit. He called this force gravity. That’s what I found out from my friend Guy Worthey, an astronomer at Washington State University. Gravity plays a big part in the answer to your question, and we’ll explore that in just a moment. Read More ...

Dr. Universe: How do horses sense how you feel? –Taylor, 11, New Zealand

When I got your question, I called up my friend and veterinarian Dr. Macarena Sanz who had just finished checking up on the horses at the Washington State University Teaching Hospital. She was happy to help. “It’s a hard question to assess scientifically,” Sanz said. “But I think everybody who has worked with horses can tell you that horses really do have a certain sense about humans.” Read More ...

Hey, Dr. Universe: Why do we humans get sunburns when we are out in the sun too long? - Gavyn, 13, Indiana 

Humans need sunlight to help keep their bones, blood and other body systems healthy, but too much time in the Sun can sometimes leave people with a sunburn. Sunburns often strike when the body gets too much of a type of light, called ultraviolet light, from the Sun. As your body recognizes there is too much ultraviolet light, it turns on a defense system. The immune system, which responds to invaders like viruses and other harmful things like ultraviolet light, kicks in. Some people might see their skin get red or blistered. They might feel itchy or painful. But not everyone experiences sunburn in quite the same way. A big part of the answer to your question also has to do with human cells. My friend Cynthia Cooper, a researcher at Washington State University, knows a lot about cells and how they work. Read More ...

Dr. Universe: How were Saturn’s rings made? -Amelia, 9, Washington State

We still don’t know exactly how the rings around Saturn formed, but scientists who study Saturn’s rings have come up with a couple of ideas. One common theory many scientists agree upon is that Saturn’s rings are made from the little leftover pieces of what used to be a moon. My friend David Atkinson is really curious about the solar system and told me more about it. He is a graduate of Washington State University and now works at the NASA Jet Propulsion Laboratory. He also worked on the Cassini-Huygens space research mission which helped us learn more about Saturn, Saturn’s large moon Titan, and the entire Saturn system. Read More ...

Dr. Universe: How do trees give us air to breathe? – Jamar, 11, Vineland, New Jersey

Our planet is home to all kinds of different plants, and they help make a lot of the oxygen we breathe. To find out how plants make oxygen, I asked my friend Balasaheb Sonawane. Sonawane is a scientist at Washington State University who researches photosynthesis, or the ways plants use energy from the sun and make oxygen. He said that in a way, plants breathe, too. “They don’t have a nose or mouth,” Sonawane said. “They have tiny microscopic organs on their leaves called stomata.” Read More ...

Dr. Universe: How does toothpaste clean your teeth? -Lucy, 10, Pullman, WA

Dear Lucy, If you are anything like me, every day you squeeze a little toothpaste onto your toothbrush and brush your teeth. Toothpaste gets its cleaning power from a few different ingredients. My friend Mark Leid was happy to tell us about how they work. Leid spent part of his career teaching future dentists. He is also dean of the Washington State University College of Pharmacy and Pharmaceutical Sciences. First, he told me the outer covering of a tooth is called enamel. It’s the hardest tissue in the whole human body—even harder than bone—and it helps with things like chewing your food. Read More ...

Dr. Universe: How do touch screens work? -Nicholas, 11, Florida

Dear Nicholas,

When I got your question, I decided to do a little experiment. First, I tapped my paw on a tablet and sent a message to a friend. Next, I put on a pair of wool mittens and started typing, but the screen did not respond. Finally, I used a banana to see if I could use it to swipe the screen. It actually worked.

I wondered what exactly was going on here and decided to take our questions to my friend Praveen Sekhar. He’s an associate professor in the Washington State University School of Engineering and Computer Science.

Sekhar told me our … » More …

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Dr. Universe: Why does oil on the street look like a rainbow? -Jorgos, 10, Bothell, WA

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 More ...

Dr. Universe: Do flying squirrels really fly? - Gwendolyn, 9

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 More ...

Dr. Universe: Why do dogs and cats spin around before they sit down? – Antonio, 10, Richmond, Va.

Dear Antonio, 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 More ...

Dear Dr. Universe: Why do some cheeses stink? – Cody, 11

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 More ...

Dr. Universe: When frost freezes, it makes shapes like flowers and ferns. Why does it look like that? - Grace, 13, in Calgary

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 More ...

Dr. Universe: Can a shadow make a shadow? – Aven, 7, Palouse, WA

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 More ...

Dr. Universe: Why do we have seasons? -Bella, 9, North Carolina

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.

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Ask Dr. Universe: Meet a Cell Biologist

In this episode of Ask Dr. Universe: Meet The Scientists, Dr. Universe interviews cell biologist Dr. Ryan Driskell, an associate professor from the School of Molecular Biosciences at Washington State University. The pair talk about what exactly a cell biologist does, how Dr. Driskell became interested in the field, other biology jobs and what Dr. Driskell thinks is the coolest, most interesting biological discovery in recent times. Plus, future scientists submitted questions for Dr. Driskell to answer, such as, what are cells and what do they do, why do we have hair and why don’t humans have hair on their palms.

Ask Dr. Universe: Meet a Geophysicist

In this episode of Ask Dr. Universe: Meet The Scientists, Dr. Universe interviews geophysicist Dr. Catherine M. Cooper from the School of the Environment at Washington State University. The pair talk about what a geophysicist does, how Dr. Cooper became interested in her field, careers in Earth Sciences and a recent discovery in geology. Dr. Cooper answers a few questions from young scientists including why are rocks gray, how do volcanoes form and what are the aftereffects of an earthquake.

Dr. Universe: How many black holes are in the galaxy and the universe? -Krisha, 9, New Jersey

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 More ...

Dr. Universe: Why do trees have sap? -Aliyah, 8, Kirkland, WA  

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 More ...

Dr. Universe: How do people stain glass to make it all the colors it can be? - Emily, 10, Edmonds, WA

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 More ...

Dr. Universe: Why does the internet go down? -Mia, 11, Sheridan, Wyoming

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 More ...

Dr. Universe: How do you make cider? -Julianna, 7

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 More ...

Dr. Universe: Why do mushrooms grow in rings? We have a lot of giant ones in our yard right now! - Layne, 8, Spokane 

When you see a ring of mushrooms, it’s likely they are exploring for food under the ground. Giant mushrooms in your backyard are not animals or plants. They are part of another class of living organisms called fungi. But like you and me, they do need food to survive. That’s what I found out from my friend David Wheeler, an assistant professor at Washington State University, who knows a lot about fungi. He said the mushrooms are just one part of fungi. The other part that explores the soil for food actually lives under the soil. Read More ...

Dear Dr. Universe: I heard a little bit about how COVID-19 started, but I don’t know much about it. What happened?  - Colleen, 10, Louisa, VA 

It turns out scientists around the world are investigating this very question. It’s likely the coronavirus that causes COVID-19, SARS-CoV-2, started in an animal before jumping to humans. But exactly how it all happened is still a kind of mystery.      That’s what I found out from my friend Michael Letko, a researcher at Washington State University who studies viruses and how they cross different species. Read More ...

How does exercise help us? What is the best exercise?

When we exercise, it helps the body and mind in so many different ways. One important muscle that benefits from exercise is the heart. Maybe you’ve felt your heart beat harder and faster when you run or climb at the playground. As the heart gets stronger, it also gets better at pumping blood around the body. That’s really important because your blood is full of oxygen you need to help fuel all your body’s systems. That’s what I found out from my friend Chris Connolly, an associate professor at Washington State University who knows a lot about the science of exercise. Read More ...

Dr. Universe: Why do we get tears when we yawn? – Ella, 8, Australia

You’re right, a lot of people get tears when they yawn. When you yawn, you actually use lot of muscles in your face. Maybe you can feel the stretch in your jaw, cheeks and eyes. As the muscles in your face contract, they can put a lot of pressure on the plumbing system that is in charge of making your tears. That’s what I found out from my friend Karin Biggs, an adjunct professor at Washington State University who teaches anatomy. Read More ...

Dr. Universe: Why do apes walk on their knuckles? - Sam, 10, Benton, Arkansas

Dear Sam, A lot of apes walk on their knuckles. Gorillas, chimpanzees and bonobos use their knuckles for stability and balance. That’s what I found out from my friend Nanda Grow, an anthropologist and wildlife biologist at Washington State University who studies primates. “Gorillas and chimpanzees both do knuckle walking, but they do different kinds,” she said. Read More ...

Dr. Universe: Why do we get pins and needles when we don't move for a long time? -Joycelyn, 9

If you’ve ever had a leg or an arm “fall asleep,” the nerves in your brain and body were sending you an important message. That’s what I found out from my friend Darrell Jackson, a researcher at Washington State University who studies how drugs affect the nervous system. The nervous system is made up of bundles of nerve fibers that help humans think, feel and navigate the world. These nerves also help people sense things like temperature, vibrations, pressure and pain. Read More ...

Dear Dr. Universe: Why do garden spiders hang upside down in the middle of their webs? -Abree, 10, New Jersey

Dear Abree,

That’s a great observation. Garden spiders and other orb-weaver spiders can crawl all around their webs, but we often see their heads pointing down toward the ground.  

My friend Todd Murray, an entomologist at Washington State University, told me about a group of scientists that had a question a lot like the one you’ve asked.

These scientists used mathematical models to learn about orb-weaver spiders and how they move around the web. They discovered spiders that wait with their head down for prey can reach prey faster than spiders that wait with head up for their prey.

While there are exceptions, … » More …

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Dr. Universe: With the coronavirus why is it effective to wear a mask? How does it make life safer? - Marin, age 12, in Ohio

Dear Marin, Whenever I go out and about, I make sure to wear my face mask. Like you, I wanted to find out exactly how they work. First, I talked to Marian Wilson, an assistant professor and nurse at Washington State University who is curious about how face masks protect people. “When we talk, sneeze, sing, or laugh, we spread droplets into the air all the time,” she said. “With the COVID-19 pandemic going on, we know people may have virus in their droplets.” Read More ...

Dr. Universe: How are gummies made? -Hayden, 11, Webb City, MO

Gummies can come in all different shapes and flavors. Maybe you’ve had gummy worms, gummy bears, or peach rings. It turns out that gummies require just a few simple ingredients. That’s what I found out from my friend Connie Remsberg, a pharmacist at Washington State University. She said making gummies requires a little gelatin, water, a mold, and some help from a grown-up. Read More ...

Dr. Universe: Why do ants build mounds? – Isabelle, 4, Eagan, MN

Ants build mounds in all shapes and sizes. Beneath those piles of dirt, ants are building their underground homes.   That’s what I found out from my friend Rob Clark, an entomologist who studies bugs on plants. His job is to figure out if bugs make a plant sick or help the plant grow.   He told me ants are one of the most diverse insect families. Scientists know about nearly 13,000 species—and each ant species makes a different kind of nest. Read More ...

Dr. Universe: Do robots have their own language? And is there a translator? - Hank, 8, Virginia

Robots do have their own language—and yes, there’s a translator. That’s what I found out from my friend Manoj Karkee, an engineer at Washington State University who is also really curious about robots. Karkee and his team work on lots of robots that help farmers do important jobs. They can program robots to do different tasks such as pick apples or pull weeds. Read More ...

Dr. Universe: How are coins made? -Dahlia, 10, Olympia, WA

In the United States, pennies, nickels, dimes, quarters, and other coins are made through the U.S. Mint. It turns out, they’ve been making a lot more coins than usual during the global pandemic. But more on that in a moment. It takes both science and art to make coins. Coins are made from metals that have been mixed together. We call these kinds of metals alloys. The very first coins in the world were made thousands of years ago in Turkey from electrum, an alloy of gold and silver. A penny is made from an alloy of copper and zinc. Read More ...

Dr. Universe: Why do we need to eat and drink? -Victoria, 7, MN

Just like a car needs gas to run, food is the body’s fuel. Food gives us energy, or the power to do work. It helps us run, jump, think, and do all kinds of things. That’s what I found out from my friend Alice Ma, a dietician at Washington State University. When you take a bite of food it goes down your throat, or esophagus, and down into your stomach. In the stomach and small intestine, things like bile, acid, and enzymes help digest, or break down your food so your body can absorb the parts it needs. Read More ...

Dr. Universe: What are bees’ wings made of? -Natalia, 13, Kennewick, WA

Dear Natalia, Bee wings may be small, but they are really strong. I learned all about bee wings from my friend Melanie Kirby, a honey bee researcher at Washington State University. Kirby said you can think about bee wings as if they were a kite. If you make a kite out of thin tissue, it might rip. But if you make it out of a strong plastic film it will be stronger. Bee wings are made of a material called chitin (KITE-IN) and it’s a lot like keratin, the material that makes up your fingernails. Chitin is what makes up the wings on each side of the bee’s body. Read More ...

Dear Dr. Universe: I am wondering if birds can smell because I have chickens and have seen their nostrils! –Lila, 9, Philadelphia, PA

Birds have nostrils, or nares, on their beaks that can help them smell all kinds of things. That’s what I found out from my friend Dave Oleyar, a scientist with HawkWatch who recently taught a course on ornithology at Washington State University. He said that when an animal breathes air, they can also breathe in different scents or combinations of molecules. The nose has receptors that pick up on scents and send information to the brain, including a part called an olfactory bulb. It’s all part of the olfactory system. You have an olfactory system, too. This system can help animals navigate the world through a sense of smell. Read More ...

Dr. Universe: Why do some birds cheep loudly while other birds cheep quietly? -Traver, 4, Indiana 

That’s a great observation. Birds make all kinds of sounds and for lots of different reasons. When I got your question, I called up my friend Jessica Tir, a graduate student at Washington State University who studies songbirds. She said one of the main reasons a bird will make a loud sound is to attract a mate. When the birds find each other, they can make a nest for their eggs and wait for babies to hatch. Read More ...

Dr. Universe: What gives leaves their shapes? Please reply back. Thanks a ton! -Pronoy, 9, San Jose, CA, USA

We can find all kinds of leaves on our planet. Just think of tiny pine needles, fern fronds, ivy vines, or a big banana leaf. My friend Eric Roalson is a professor at Washington State University who is very curious about plants. He said there are a few things that give leaves their shapes. The shape of a leaf can depend on the family history of a plant, the group it belongs to, and the environment where it grows up. Read More ...

Dr. Universe: Here is my question. How is paper made? I asked this question because there are different kinds of paper and I'm curious about how it is made. Sincerely, Sonakshi, 9, Michigan

We can make paper in lots of different ways. It often starts with trees. In fact, one of the first kinds of paper we know about was made in China using rags, plants, and bark from mulberry trees. These kinds of materials are made up of parts called fibers. Fibers are what help give plants strength to stand up. Humans who eat plants like lettuce or celery have actually eaten some of these fibers. A lot of the clothes we wear come from plant fibers, too. Plant fibers are called cellulose. Humans aren’t able to digest these fibers because they are really hard to break down. But strong fibers are great for making paper. Read More ...

Dr. Universe: Why does soap get bubbly? Samuel, 9, East Peoria, IL

When you wash your hands with soap and water, a few different things happen to make bubbles. Just like you, water and soap are made up of parts called molecules. Water molecules really like to stick together. If you’ve ever jumped in a puddle or a pool, you may have even observed how water splashes in the shape of little drops. As water sticks together, it likes to form spheres. Read More ...