Dear Prince,

Germs are tiny organisms—also called microbes. They’re so small you have to zoom in with a microscope to see them. They can be bacteria, viruses, fungi or other teeny things. Some microbes make us sick. Some don’t bother us at all. Some help us out.

I talked about all that with my friend Eric Lofgren. He studies infectious disease at Washington State University.

He said there are two main reasons we have germs on our skin. We pick up some microbes from the environment. Some live on our skin all the time.

“The world is full of microbes,” Lofgren said. “They’re very … » More …

Dear Prince,

When I was a kitten, I saw a movie about shark attacks. It made me nervous to go into the water.

I talked about that with my friend Nora Hickey. She’s a fish veterinarian at Washington State University.

She told me that sharks don’t eat people.

Many sharks can’t even bite. They have mouths adapted to sift sand or slurp up plankton.

Sharks that can bite don’t hunt humans. They eat prey with a thick fat layer like seals and sea lions. Muscly animals like birds, cats and people seem to taste bad to sharks.

“Even if they bit you, … » More …

Dear Colleen,

When I was little, I liked to move the radio dial in the car. I could hear different channels with music or talking. Plus, static in between.

My friend Ben Belzer reminded me of that when we talked about your question. He’s an engineer at Washington State University.

“Your cell phone is basically a digital radio,” Belzer said.

Any place with cell phone coverage gets divided into cells. They could be six-sided hexagons like the cells in a beehive. Or they could be any shape with flat sides. The size of the cell depends on how many people live there. A … » More …

Dear Carlos,

Your question almost stumped me. I don’t really have dinosaur scientist pals. So, I turned to an expert on finding answers.

My friend Emily Cukier is a science librarian at Washington State University. She helps students and scientists find information. I asked her what dinosaur is the largest—and how she figures that out.

Cukier told me that I should think hard about my question. Are we looking for the tallest dino? The longest? The heaviest? Those might be different answers.

Then it’s time to ask the internet.

“I’m a librarian, but the first thing I would do is put it into … » More …

Dear Jacob,

I love vaccines. They keep us safe from germs that can make us sick. But I don’t love how much shots hurt. Sometimes I feel anxious before I visit the veterinarian for a vaccine.

I talked about that with my friend Roland Chen. He’s an engineer at Washington State University.

He’s working on brand-new needles that could make shots painless. They’re called microneedle arrays.

“You feel pain because the needle reaches the pain receptor,” Chen said. “Microneedles are much shorter than typical needles. They’re about one-third to half the size.”

Most vaccines are intramuscular injections. A trained healthcare provider gently slides … » More …

Dear Malachi,

Sometimes animated turtles seem to live inside their shells like it’s a tiny home. They may even hop out of the shell and run around.

That’s funny in cartoons and games, but my friend Ryan Wagner told me it could never happen in real life. He’s a wildlife biologist at Washington State University. He studies animals like turtles and frogs.

It turns out that a turtle’s shell doesn’t sit on top of its body. It’s part of the turtle’s body.

“Turtles are their shells,” Wagner said. “The shell is made up of their bones. As the turtle grows, its shell … » More …

Dear Anika,

My roommate is a normal cat. When she needs a treat, she smacks her lips. When she wants outside, she paws the door. But she never talks to me using words.

I asked Nancy Bell how my human friends developed language. She studies linguistics at Washington State University.

Bell told me that we don’t know exactly how or when it all started. All kinds of scientists want to figure that out.

“It’s just part of our species that we want to make meaning,” she said. “We want to communicate. That desire is what leads to language.”

Scientists use the word “hominin” … » More …

Dear Nghi,

When you and I take a deep breath, we pull air into our lungs. That’s because humans and cats are mammals. But fish aren’t mammals. They usually don’t breathe air. They usually don’t have lungs.

That’s what I found out from my friend Michael Berger. He’s a biologist at Washington State University.

He told me that you can actually see a fish breathe water. Its face gets bigger when it takes in a big gulp of water. Just like when you take a big bite of food.

When you look at a fish, you can usually see the gill openings—called gill slits. … » More …

Dear Joie,

After answering science questions all day, I like to play Mario. It’s relaxing to smash Goombas and zoom down pipes.

I asked my friend Dene Grigar if that’s wrecking my brain. She leads the Digital Technology and Culture program at Washington State University Vancouver.

She told me that sometimes people dismiss new things by calling them harmful.

That often happens with new technology or media. People reacted that way to railroads, telephones, cameras and television. People even freaked out about books. For a long time, books were hard to come by, and regular people couldn’t read. When that changed, folks worried about … » More …

Dear MacKenzie,

A neutron star is what’s left after a massive star runs out of fuel and explodes as a supernova.

I asked my friend Matthew Duez about it. He’s an astrophysicist at Washington State University.

He told me that a neutron star is the densest known object in the universe. Its mass is like the sun’s mass. But a neutron star is the size of a city.

When something is dense, it has lots of stuff—or mass—crammed into a small space.

Imagine if we took all the humans on the planet and squished them together. We mash and squash them until they fit … » More …