Dear David,

I love visiting with my grandcat. But sometimes I have to talk loudly so she can hear me.

I asked my friend Christine Portfors why that is. She’s a biologist at Washington State University.

She told me it’s all about the hair cells inside our ears.

They aren’t really hairs. They’re sensory cells. Hair cells have tiny, bristle-like tufts that stick out—called cilia—that look a little bit like hairs.

Those hair cells are why we can hear.

First, sounds funnel into our ears. They bonk into the ear drum and make it vibrate. Then, three itty, bitty bones make those … » More …

Dear Grady,

I was exploding with excitement to ask my friend Guy Worthey about supernovas. He’s an astronomer at Washington State University.

He told me a supernova is a very energetic explosion in space.

There are different kinds of supernovas. One kind—called a type II supernova—happens when a really big star dies.

“Why would a star bother to blow up?” Worthey said. “It seems dramatic. Human beings don’t blow up when they die.”

But humans don’t have cores that do nuclear fusion. Deep inside a star, protons and neutrons bang together and make new chemical elements. That nuclear fusion is why stars shine.

… » More …

Dear Carmen,

Right now, there’s a fly walking on the window in my office. I asked my friend Rich Zack how it does that. He’s an insect scientist at Washington State University.

It turns out my window isn’t as smooth as it looks. If we zoomed in on the glass, we’d see bumps and dips. It’s kind of like a rock face or a climbing wall.

“Surfaces look pretty smooth,” Zack said. “But if you get really, really close, you see there are all kinds of little indentations and crevasses. Even a pane of glass is not perfectly smooth. It’s got little nicks and … » More …

Dear Braelyn, 

Everyone feels grumpy sometimes—even a cheerful cat like me.  

Sometimes exhaustion makes us crabby. When we really need sleep, our brains struggle to do their jobs—like managing our emotions. Sometimes hunger makes us cranky. Our brains need a steady supply of sugar energy. When the available sugar drops too low, we feel terrible—or even hangry. Sometimes stress or problems like anxiety and depression make us grumpy. 

In all those scenarios, anger lets us know we need to change something. We need to sleep, eat or get some help with our problems.  

I asked my friend Anthony Lopez why we feel anger … » More …

Dear Haygarth,

I love glow-in-the-dark stickers. I leave them next to a sunny window for a little while. Then turn off the lights and watch them glow.

I asked my friend Hergen Eilers how those stickers work. He’s a physicist at Washington State University.

He told me that glow-in-the-dark things use a type of phosphorescence. That means they absorb energy—like light—and then glow. A material that can do that is called a phosphor.

Glowing in the dark works because of electrons.

Everything in the universe is made of atoms. That includes you, me, whatever you’re reading this note on—and glow-in-the-dark stickers.

All those … » More …

Dear Remmi,

Mars is about 140 million miles from our cozy planet. A human mission to that cold, rocky neighbor would mean being away from Earth for about 3 years. But the things those explorers would see and learn would be mind-blowing.

I asked my friend Katie Cooper about that. She’s a scientist at Washington State University. She studies how geology and physics work on Earth and other places in space.

She told me the weirdest thing on Mars is a ginormous volcano.

“Olympus Mons is the largest volcano in the solar system,” Cooper said. “It dwarfs Earth’s volcanoes! Its massive size helps … » More …

Dear Dean,

There’s a pencil lying on my desk right now. It’s not much to look at, but what if I could zoom way in and see the protons and other itty-bitty stuff inside it?

My friend Ryan Corbin told me it would be like looking at a bubbling soup of fundamental particles. He’s a quantum physicist at Washington State University.

He told me that protons—along with neutrons—form the nucleus in the middle of an atom.

“Atoms make up all the stuff that we see,” Corbin said. “An atom has neutrons and protons in its nucleus. Protons have a positive electric charge. Neutrons … » More …

Dear Zara,

I love visiting the vet. But, like many cats, sometimes I need medicine to keep me calm.

I talked about that with my friend Lais Malavasi. She’s a veterinarian at Washington State University.

She told me about two kinds of calming medicine. Vets and human doctors use them to reduce pain and fear.

Sedatives make patients feel relaxed and sleepy. But they’re mostly aware of what’s going on. When the medicine wears off, they’ll probably have fuzzy memories.

Anesthesia makes patients unconscious. They can’t feel pain or move. They aren’t aware of what’s going on. When they wake up, they won’t … » More …

Dear Dru,

When it comes to intestines, it sure seems like two are better than one.

I asked my friend Franck Carbonero why that is. He’s a microbiologist at Washington State University. He studies the bacteria that live inside the human gut.

He told me that the small intestine and the large intestine do different jobs.

Let’s say you sink your teeth into some pizza. You chew it up and swallow it. All those chewed up bits land in your stomach. They mix with digestive juices and start to break down. The broken-down food and digestive juices together are called chyme. After … » More …

Dear Lucy, 

Cats like me don’t have wisdom teeth. So, imagine my surprise to learn some of my human buddies get extra chompers. 

I asked my friend David Carsten about it. He studied biochemistry at Washington State University. Now he’s a dentist who teaches about dental sedation and anesthesia at Oregon Health & Science University. 

Dr. Carsten told me that humans can get three sets of permanent molars. Molars are the big grinding teeth in the back of your mouth. The third set—also called wisdom teeth—usually come in when you’re between 17 and 21 years old. If you get them at all. 

Wisdom … » More …