Why do we have water in our bodies? –Angelika, 12, Cathedral City, CA
Believe it or not, we are mostly water. Of course, you may have noticed we aren’t sloshing around and spilling everywhere. » More …
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.
Dear Dr. Universe: How do our ears work? -Aryana, 11, Ohio
The chirps of birds. The squeaks of mice. The barks of dogs. In a world full of different sounds, our ears take in almost everything. But it takes more than just our ears to hear. » More …
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
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.