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Why can’t we just print a bunch of money to make everyone rich?

Why can’t we just print a bunch of money to make everyone rich?

– Daniel, 8

Dear Daniel,

It sure sounds like a nice idea. Print a bunch of money and everyone gets rich. We could buy anything we wanted. Ah, if only it were that easy. It turns out printing more money would have a much different outcome than we might like to imagine. » More …

What does a planet have inside?

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.

Even deeper in our planet is the core. It’s made up of metals, like nickel and iron. In fact, at the center of Earth there may be a ball of solid nickel and iron. It’s a solid because of the intense pressure there. But the outer part of the core is under less pressure, so it’s likely more fluid.

You may have heard that Earth is like one big magnet. It’s the reason why our compasses point north. Scientists think that as Earth’s fluid interior swirls around with the spin of Earth, it helps generate the planet’s magnetic field.

Earth’s magnetism is also part of the reason we have the Northern Lights. When particles from the sun strike particles in our atmosphere near the Earth’s magnetic field, it can create colorful displays.

While we can see some of the ways deep earth shapes our planet, we can’t actually look inside it. The deepest scientists have ever explored is about 5 miles into the Earth. Since we can’t slice up a planet, scientists use different measurements to figure out what’s going on.

One way they do this is to look at waves that earthquakes produce. Scientists can use seismometers, machines to measure the shaking of the ground, to help measure the waves. Some of these waves only move through solids, like the inner core. Others move through solids and liquids, like the outer core and mantle. They can use this information from the wave measurements to put together a better picture of the planet’s composition.

Other rocky planets—Mercury, Mars, and Venus—likely have similar interiors to Earth’s. It appears Mercury has the biggest core, at least compared to its size.

Then there are the giant gas planets: Neptune, Saturn, Jupiter and Uranus.

Air is one gas we all know. We breathe it. Planes zip through it. Each of these planets in the outer solar system is surrounded by different gases. We couldn’t stand on them.

If we did travel through the center of a gas giant, we would probably find something pretty familiar to our own rocky planet on the inside.

Your friend,
Dr. Universe

 

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Correction: An earlier version of this article described the mantle as big slush ball of hot liquid magma and minerals. This has been updated to a more accurate description of the mantle.

Does science get harder every year or is that just me?

Does science get harder every year or is that just me?

-Keegun, 8th grade, E. Wash.

Dear Keegun,

We’ve got about three pounds of brain in our heads that help us look for answers and solve all kinds of problems. But it isn’t always easy. Sometimes an experiment doesn’t go the way I expect or I get stuck on a particularly tricky science question. » More …

How do I program a computer?

How do I program a computer? –Ammon, 11, Magna, UT

I have some really cool game ideas. I want to learn to program and animate web sites. Do you have any ideas on how to get started? – Tyler, 10, Suisun City, CA

Dear Ammon and Tyler,

Everything our computers do, they do because we program them to do it. Maybe you want to design a game or an app that’s brand new. To create that game or app, you have to help your computer understand what to do.

And to do that, you have to learn its language. That’s what I found out from my friend Gina Sprint, a computer scientist at Washington State University. She’s really curious about how machines learn and how we can use technology to improve health.

“Our computers don’t understand English. If we want to communicate with our computers, we have to speak their language,” Sprint said.

She showed me a way to start learning about computer code with a program called Frozen Fractals. You can try it out, too. You use the programming language called Python to direct a little turtle that draws out different shapes. I was wondering how the computer knew how to respond to the directions.

“The language that computers understand is called binary. We write code in a programming language similar to English, like Python, that is translated into binary so the computer understands,” Sprint said.

Binary means you have only two options to communicate. Believe it or not, pretty much everything we program our computers to do comes back to just these two things.

In a computer, wires carry information through the machine in the form of electricity. The computer can make the electricity stop or go, switch it on or off, by recognizing zeroes and ones. Different combinations of ones and zeroes can correspond with different letters, too.

While we might say cat in English, a machine would spell out “cat” as 01100011 01100001 01110100. That’s the language of binary.

One way you can start programming and learning more about binary is with a visit to Code.org, Sprint adds. It is an organization headquartered in Seattle but anyone, anywhere can learn how to program through the website.

The main job of coders is to create programs, but a lot of time is spent fixing them. Sometimes things go wrong with your programming. You might get a bug in your code. That’s when you get to be a problem solver and fix the error. The term “bug” was popularized in 1945 by the computer scientist Grace Hopper, said Sprint. Hopper actually found a moth in her computer. Now we use the word bug to talk about problems in the code.

Remember, a computer works because of code written by a programmer. A computer knows what to do because we help it understand. Who knows, maybe one day you’ll study computer science. But really, there’s no need to wait. You can get started right now at Code.org. Sprint and I can’t wait to hear about what you learn and create.

Your friend,

Dr. Universe

Why does stuff decay?

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.

There are a lot of living creatures in nature that help break down things. In fact, our trash cans are almost like an all-you-can-eat-buffet for tiny creatures called microbes. Well, an almost all-you-can-eat-buffet. There are some things that they can’t really feast on. It all depends on what’s in our trash bins.

For billions of years, microbes have been munching on plants and animals. They’ve also had some help from fellow decomposers, like worms, flies, and fungi.

The environment where they work can also speed up or slow down the process. The conditions of dirt, air, water, temperature, and sunlight can change the speed of decomposition.

These decomposers are pretty great at breaking down a lot of things we find in nature. But they aren’t as good at breaking down some other materials, such as plastic.

To find out why, I visited my friend Shuresh Ghimire, a scientist who studies biodegradables at Washington State University. He is also really curious about finding ways to decrease the amount of plastic waste in our world, particularly on farms.

Plastics were introduced in the 1930s, he explained. Now, that may seem like a long time ago to us. But for microbes that have been around for billions of years, that’s still a pretty new material.

Both an apple peel and a plastic bottle are made up of different kinds of atoms. Those atoms are bonded and held together in different ways. In an apple, the bonds between atoms are pretty weak. Microbes don’t have to use a lot of energy to break them into smaller parts.

But the plastic bottle has really strong bonds—especially where a carbon atom bonds with another carbon atom. It makes the material sturdy, but it also makes it pretty indestructible. Most microbes don’t recognize these bonds as something they can break down, at least not yet.

“There is a possibility that evolution of microbes over many years in the future may enable more of them to recognize bonds in plastics,” Ghimire said.

In fact, a group of scientists in Japan recently discovered a microbe that looks to be pretty good at eating plastic. They might be able to help us manage some of the plastic waste, but we can help, too.

A water bottle might last hundreds of years buried underground or in a land fill, but it could have a new purpose in our own lifetime if we remember to reuse or recycle it.

Sincerely,
Dr. Universe