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Ask Dr. Universe rcwebber

Dr. Universe: How do cacti survive in such hot and dry environments?

-Ravin, 11, London, England

Dear Ravin,

All plants need water to survive. Those that live in places where water is scarce use some interesting strategies to stay alive.

That’s what I found out from my friend Charles Cody, who manages one of the greenhouses at Washington State University. When I went to visit the greenhouse, he pointed out a few different cacti.

One was tall and cylindrical with big spines. Another was small and round with what looked more like little hairs. A rainforest cactus hung on the wall like a vine.

Cody explained that if … » More …

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Dear Dr. Universe: What happens to the world’s garbage? -Presley, 8, Spokane, Wash. How do you recycle an object into another object? -Brianna, 12, New York

Dear Presley and Brianna,

So far, we’ve investigated how recyclables like plastic, aluminum, and paper can end up in the trash. If our clothes get damaged, or we simply outgrow them, we might toss them in the trash, too. Or send them to a thrift shop. Either way, they often end up buried in a landfill.

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Dear Dr. Universe: What happens to the world’s garbage? -Presley, 8, Spokane, Wash. How exactly do you recycle an object into another object? -Brianna, 12, New York

Dear Presley and Brianna,

While a lot of our trash goes in a landfill, we can also recycle all kinds of stuff on our planet. Depending on what the object is made of, we might grind it up, mix it up or melt it down before we turn it into something new.

Let’s start with paper. When you recycle paper, it usually ends up at a recycling center where it gets washed with soapy water and mixed into a huge, thick slurry.

Sometimes we add a few other ingredients if we want a specific kind of product, like cardboard or printer paper. The slurry is … » More …

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Dr. Universe: Do you have any experiments you can recommend? Thanks! -Etta, 7, Milwaukee

Dear Etta and Friends:

You can try all kinds of fun experiments at home. It really all depends on what you are curious about. Lately, I’ve seen some really great sunsets and started wondering what gives them their colors.

I decided to ask my friend Tom Johnson, who leads fun physics demonstrations for kids visiting Washington State University. I asked him if he had any simple ideas for an experiment I could try out in my lab, or even the kitchen. One idea he had was to create a sunset in a cup.

Maybe you can try it, too. You’ll need a flashlight, a … » More …

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Can video games help us learn? - Isaac, 12, Clyde, N.Y.

Dear Issac,

All kinds of games can help us learn, including some video games. They can be a fun and useful way to help you remember what you learn, too.

Our brains work hard each day to take in and process information. Ever since video games were invented, people have been asking if and how they might change our behavior and brains.

For example, people once thought that video games left players with poor eye-sight and poor attention. Some scientists decided to actually test out these ideas. Their studies have shown that some video game players … » More …

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Dear Dr. Universe: Why does hair turn gray? –Darae, 10

[caption id="attachment_2942" align="alignleft" width="592"] Dr. Universe examines a gray hair.[/caption]

Dear Darae,

Hair comes in lots of different colors. There’s black, medium brown, auburn, light brown, strawberry blonde, and copper, to name just a few. But in the end, almost everyone will have hair that’s gray or white.

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Dear Dr. Universe: How does a light bulb work? When one bulb in a string of lights goes out, why do they all go out? – Molly, 8

Dear Molly,

Just the other day I was taking down a string of lights from my lab, when I discovered the bulbs were burnt out. I visited my friend Aaron Crandall, an engineer at Washington State University, to see if I might get them working again.

Crandall explained when you plug in a string of lights to a power source, like an outlet, an electrical charge flows into the wires. A lightbulb works when an electrical current runs through thin metal wires in the bulb and electrical energy gets converted to heat and light. We can get this current of electricity to follow different paths, … » More …

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Dr. Universe: How is glass made? And, what is it made out of? What about thick glass like they are putting up on the Space Needle? – Tali, almost 8 years old, Seattle, Wash.

Dear Tali,

We can make glass in factories and we can find it in nature. Some volcanoes make glass. When they spew out lava, it often cools into obsidian, a black glass. Glass can also form on sandy beaches. Small tubes with smooth glass on the inside may appear after super-hot lightning strikes the sand.

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Dr. Universe: How do planes fly? -Tahira, 12, India

Dear Tahira,

Planes are very heavy, yet they stay up in the air kind of like a bird in the sky. They can get us across the world in less than a day. Humans went from learning how to fly a plane to putting a man on the moon in a little over 60 years.

But the answer to your question goes even further back. It goes all the way back to the 1700s and actually started not with air, but with water.

That’s what I found out from my friend Michael Allen, a physics and astronomy professor at Washington State University. He thought you … » More …

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Hello Dr. Universe, may I ask how fish breathe? - Nghi, 11, Vietnam

Hello Nghi,

Cats, humans, and fish all breath for the same reason. We need oxygen. Oxygen is one of the things our bodies use to make energy.

Just like the hungry feeling you get when you haven’t eaten, your body uses oxygen to keep everything running. Unlike the breaks you take between meals, the breaks you take between breathes are much shorter. Most people take about 12 breaths per minute.

While it may seem like we breath only oxygen, there are lots of other gasses in the air. When we breath in, our lungs fill up with all this gas. The lungs take the oxygen … » More …

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Dr. Universe: Why do birds have feathers? –Karthikeya, 7

Dear Karthikeya,

Bird feathers are interesting. There are so many types, shapes, and colors. My friend Daniela Monk is a Washington State University professor who studies avian ecology, or the study of birds.

She told me about why the birds we know today have feathers and how they got them. Researchers believe that birds evolved from dinosaurs a very long time ago.

“One lineage of dinosaurs gave rise to birds,” Monk said.

Researchers around the world are finding dinosaur fossils that contain feathers. A fossil is the remains of a very old animal or plant that is preserved in a rock. From these fossils they … » More …

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The Curiosity Corner

Every smart science cat needs a great sidekick. Student science writers in the Murrow College of Communication help Dr. Universe connect K-8 students with researchers at Washington State University.

Why do people like to listen to songs over and over? – Daniel, 13, Richland, WA

By Cameron Sheppard

We don’t just use our ears to hear music. A big part of hearing also has to do with our brains. Our ears certainly are necessary to help us hear, but it is our brain that helps interpret the sounds in our environment.

» More …

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Hi Dr. Wendy Sue: Me and my brother had a little bit of an argument about the point that there is no such thing as cold. He said liquid nitrogen produces cold, which I think is absurd, but lack the knowledge to explain it. Can you please explain to us why there is no cold? – Brody, 12

Dear Brody,

It’s a snowy morning and the thermometer reads 20 degrees Fahrenheit. You grab a jacket and a pair of mittens for your paws. It’s going to be a cold day.

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Dr. Universe: In space, which way is up? –Pablo, 10, Spokane, WA

Dear Pablo,

We might not always think about it, but every day gravity keeps us pulled to the Earth. It’s what brings us back down when we jump on a trampoline. It’s why a Slinky tumbles down stairs.

Now think about what it would be like to live in a place with very little gravity. Let’s say you were 200 miles off the ground, orbiting earth in the International Space Station. Here, the idea of up and down really gets flipped around.

On Earth, the human balance system helps the head figure out how move up … » More …

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Dear Dr. Universe: Why is the map the way it is? - Pablo, Spokane, Wash.

Dear Pablo,

Next time you eat an orange, try getting the peel off in one piece. Next, try to flatten out your peel. You’ll likely find it a bit tricky to make something round perfectly flat.

The same is true when we map our three-dimensional world onto a flat surface. It doesn’t work very well. That’s what I found out when I went to visit my friend Rick Rupp, a Washington State University researcher.

Rupp is an expert on geographic information systems, which can help us capture and analyze the geography of our planet. He explained that maps can show us all kinds of … » More …

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Dear Dr. Universe: I have a question for you about ants. From what I searched on Google, an ant has a nervous system, blood, open circular system, muscles, and a brain. So, Dr. Universe, the question is, do ants or other insects get headaches? Cause they work hard. –Joseph, 14, Singapore

Dear Joseph,

If you’ve ever had a headache, it might have felt like pain was radiating right out of your brain.

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Dr. Universe: Why are there different blood types? - Sarah, Tacoma, Wash.

Dear Sarah,

At this very moment, several quarts of blood are circulating through your body at nearly 4 mph. But as you’ve pointed out, not everyone’s blood is the same.

Your question made me wonder exactly what we mean when we talk about blood types. I decided to ask my friend Amber Fyfe-Johnson, a researcher at Washington State University who studies cardiovascular diseases--diseases of the blood vessels-- in kids.

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Dear Dr. Universe: HOW DOES WATER IN THE OCEAN MOVE? I THINK IT’S BECAUSE OF THE WIND. –Case, 5, Yakima

Dear Case,

You know, most cats like to stay a comfortable distance from water.

But when I got your science question about our big ocean, I was ready to jump right in.

Ocean water moves in all kinds of ways. Waves curl and crash on the shore. Big conveyer belts of water, currents, flow for thousands of miles around our planet. The tides go out and come back in.

And yes, the wind plays a big part in all of it. That’s what I found out when I went to visit my friend Jeff Vervoort, … » More …

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Hello Dr. Universe: I was wondering, how does an eclipse happen? - Susan, 13, San Francisco, CA

Dear Susan,

It just so happens the Great American Eclipse is coming up on Aug. 21, 2017. This solar eclipse will be the only one visible from across the lower 48 states in nearly a hundred years. When it happens, parts of the country will experience darkness for a couple minutes during the day.

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Dear Dr. Universe: I would like to find out how ants are so strong. How is it possible that they can carry weight that is heavier than themselves? –Anita, 11

Dear Anita,

Ants are pretty good little weightlifters. My friend Rich Zack, a scientist at Washington State University who studies insects, knows a lot about ants. One kind of ant that he has studied can carry up to 20 times its own weight.

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What do astronauts eat in space? –Rhemi, 12, St. Louis, Mo.

Dear Rhemi,

Astronauts eat all kinds of different foods up in space. The food is often similar to what we have here on Earth. But in space, there's very little gravity. There’s very limited refrigeration, too. On the International Space Station, the refrigerator is only about half the size of a microwave. That means scientists who prepare and package astronaut food have to do it in ways that take up very little room and don’t need to be kept cold.

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Dear Dr. Universe: When will the next major earthquake be? Earthquakes really interest me and I want to know so I can be prepared when the next major quake happens. - Carmen, 11, Chowchilla, Calif.

Dear Carmen,

Our planet’s surface is constantly on the move. Sometimes this movement really shakes things up.

The Earth’s crust is made up 14 major pieces and dozens of smaller ones, called plates, that move in super slow motion. Earthquakes can happen when these plates suddenly slip past each other. They send out waves of energy that make the ground shake.

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Dear Dr. Universe: What causes lightning? -Monica, 10, Costa Rica

And while we’re at it, let’s answer these questions:
When lightning strikes the ocean, what happens to the fish? –Olivia, 12, Manchester, UK
Why is lightning attracted to metal objects? –Grant, 11, Pullman, Wash.
Why does lightning sometimes just happen in clouds? –Leo, 11, Cayman Islands
 
Dear Monica, Olivia, Grant, and Leo:
While you are probably not in the middle of an electrical storm right now, there are more than 1,000 happening at any given moment on our planet. They happen on Saturn, Venus, and Jupiter, too.  

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Why do we have different feelings? - Charan and Aishwarya V., 10 & 8, Rutherford, New Jersey

Dear Charan and Aishwarya,

Imagine you are playing a game of soccer and your best friend is on the opposing team. The sun is out, you are having a great time, and you score the winning goal. You’d probably feel pretty happy and so would your team.

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Why does meat get brown on the grill? – Christina, Seattle, Wash.

Dear Christina,

You know summer is just around the corner when the smell of barbecue is in the air. It’s a great question you ask and it leads us to the Meats Lab at Washington State University. That’s where I met up with my friend and animal scientist, Jan Busboom.

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Dear Dr. Universe: What do planets have inside? -Rhianna, 10, Calif.

Dear Rhianna,

Each planet is a little different on the inside. And what’s inside a planet can shape what’s on the outside, too. That’s what I found out from my friend Steve Reidel, a geologist at Washington State University.

“Well, there’s the rocky planets,” he said. “Then there are the big, gas giants.”

Rocky planets, like Earth, are wrapped in a thick crust. Beneath Earth’s crust is the mantle. The mantle is quite solid, but it actually behaves more like a fluid. It flows and deforms. It’s similar to Silly Putty, but a really strong version of Silly Putty. It’s about 1,800 miles thick. It is also the main source of Earth’s volcanoes.

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Dear Dr. Universe: What exactly is climate change? How does it affect the way we live? –Pranav, 10, Melbourne, Fla.

Dear Pranav,

If you’re anything like me, one of the first things you'll do in the morning is check the weather. Sometimes it’s rainy and I’ll put on my rubber boots. Other days it’s really sunny and I’ll grab my sunglasses. When we look at the patterns of these weather conditions over a long time—sometimes over hundreds of years—we can learn about a place’s climate.

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Hello! My name is Daiwik and my question is "Why are stars in space? Why are they needed? Can they be made on Earth?" No one I know knows the answer to this. Can you find out for me?- Thanks, Daiwik P.S. You're awesome!

Dear Daiwik,

If you are anything like me, you like watching the night sky. The stars we see are a lot like our nearest star, the sun. They are just much farther away. That makes stars look like small twinkly things instead of a big, furious thing like our sun.

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Dear Dr. Universe: Do you know how human and animal interactions help our mind grow? Does it help us? Does it do nothing? This has fascinated me for a very long time. - Gabby G., 11, Berlin, VT

Dear Gabby,

Our brains are pretty busy. They are constantly thinking, feeling, and sensing our world. One thing that can help some people relax is spending time with an animal friend. You might play fetch with a dog, sit with a cat, brush a horse, or even watch a goldfish zip around its bowl.

People who spend a lot of time with animals might tell you that something special seems to be going on here. But scientists are looking for evidence and want to find out for certain just what is going on. They want to know … » More …

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Dear Dr. Universe: We have a lawn full of clovers that bumble bees love. Where do bumble bees live? Do they have hives or live underground? I love watching them. Do they live through winter? –Karen, Arizona

Dear Karen,

When it comes time for bumble bees to find a home, it’s pretty much up to the queen bee.

That’s what I found out from my friends Rachel Olsson and Elias Bloom. They are graduate student researchers here at Washington State University and really curious about bees, too.

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Dr. Universe: I have a ginormous question for you. How come non-biodegradables take like a million, billion, zillion years to decay? -Madeline C., age 8

Dear Madeline,

You’re right. It can take a really long time for some things to decay.

If we buried an apple peel in the backyard it might only take a few weeks to break down into the soil. But if we buried a plastic water bottle, it would probably still be there hundreds of years from now.

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Dear Dr. Universe: I was just wondering if there are any volcanoes on any other planets? Danny, 10, Kenmore, WA

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Dear Danny,

The answer to your question takes us out into our solar system and deep below the surfaces of other moons and planets.

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Dear Dr. Universe: Why do we find some things scary? -Jack H., 8, UK 

Dear Jack,

While our fears might be different, we all get scared sometimes. Vacuums, dogs, and even cucumbers make my hair stand on end. Perhaps for you it’s spiders, the dark, or the thought of monsters under your bed.

My friend Michael Delahoyde is really curious about what freaks us out. As an English professor at Washington State University, he’s even taught a course about monsters.

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How do spiders make silk? And other questions to explore in October

How do spiders make silk?

Spiders can do some amazing things with their sticky, stretchy, and super-strong silk. Us cats are pretty curious about these little silk-spinning machines, too. Besides chasing spiders around, I’ve watched them use silk to build webs, catch bugs, and protect their young spiderlings.Screen Shot 2016-04-04 at 9.05.13 AM

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Do bats have habits?

You are onto something. Quick, to the bat-lab! That’s where I met up with my friend Christine Portfors, a scientist at Washington State University who studies fruit bats.

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Why … » More …

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