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How do scientists know how to predict a solar eclipse?
Before humans even knew how to predict solar eclipses, they were fascinated with the phenomenon. To figure out how to predict an eclipse, astronomers asked lots of questions and made observations about the motion of our moon, sun and Earth.Read Story
What bacteria make us get stomach bugs?
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.Read Story
Why do we find bones in rock?
When humans want to look into the past, they often dig into the ground. Under the soil, archeologists can find all kinds of things that help us learn about life long ago.
That’s what I found out from my friend Rachel Horowitz, an archaeologist at Washington State University who is very curious about the lives of our human ancestors.Read Story
Why do animals have different hearing?
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.Read Story
Why do leaves fall in the fall?
Dear Kaitlyn and Aiden,
You’re right, each year during the fall, we often see a lot of trees dropping their leaves. To find out exactly what happens when leaves fall, I talked to my friend Henry Adams, a researcher at Washington State University.Read Story
How did the sun form?
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 …Read Story
What’s the purpose of baking soda and baking powder?
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 Story
What are the strings inside a pumpkin?
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 …Read Story
Why can’t we breathe in space?
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 Story
Sleep: Why does sleep feel short?
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 Story
What happens when a bee stings you? What happens to the bee?
A few different things happen when a bee stings you, and a few things happen to the bee, too.
When I got your question, I called up my friend Brandon Hopkins, who works as a honeybee researcher at Washington State University.Read Story
How do human hearts beat?
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.Read Story
What are cells made of?
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 Story
How do memory cards work?
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 Story
When and why would a clam open its shell?
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 Story
What happens in our brain and body when we hear a funny joke?
When we hear a funny joke, there are lots of different things that happen in the brain and body. My friend Paul Bolls, the director of the Media Mind Lab at Washington State University, told me all about it.Read Story
How do we clone things?
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 Story
How do lungs work?
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 …Read Story
What is more effective, a face mask or a face shield?
If you are like me, you’ve probably seen people wearing face masks, face shields or even both at the same time.Read Story
Why do astronauts need astronaut suits?
When astronauts leave Earth, a spacesuit can help them stay safe in places that are quite different from their home planet.
I learned all about it from my friends Stasia Kulsa, Lauren Reising and Ian Wells, a few members of a team at Washington State University researching how to clean moon dust from spacesuits.Read Story
Why do we have to keep things like ice cream and popsicles in the freezer?
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.Read Story
What are some of the challenges of growing organic food?
There are all kinds of different things to think about, along with a few challenges, when it comes to growing organic food.
My friend Lynne Carpenter-Boggs is a soil scientist at Washington State University who works with many different farmers and knows a lot about what it takes to produce food that is organic.Read Story
How do mountains form?
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.
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.Read Story
Why do we have to blink?
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 Story
How do tiny seeds make huge trees?
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 Story
Why does it make noise when you snap your fingers?
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 Story
Why are some berries poisonous?
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.
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 Story
Trees: Why do they grow so slow?
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 Story
How do you learn something really, really hard?
There are so many different things we can learn in our world, but that doesn’t mean learning is always so easy. Maybe you want to learn a process, like how to complete Rubik’s cube, code an app, design a solution to a problem or answer science questions.Read Story
Worms: How do they help the dirt?
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.
“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 Story
How do fish migrate and why?
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 Story
Why are people most commonly right-handed?
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 Story
How did people figure out how much a whole planet weighs?
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 Story
How do horses sense how you feel?
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 Story
Why do we get sunburns?
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 Story
How did Saturn’s rings form?
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 Story
How do trees give us air to breathe?
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 Story
Dr. Universe: How does toothpaste clean your teeth? -Lucy, 10, Pullman, WA
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 Story
Why do we get goosebumps?
If you’ve ever been outside on a cold day, you may have noticed how your arm hairs stood up and you felt some goosebumps.
Humans get goosebumps for different reasons and one of those reasons has to do with temperature.
My friend Ryan Driskell, an assistant professor at Washington State University, is really curious about the innerworkings of skin.Read Story
How do touch screens work?
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 …Read Story
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