Hi there! Have you ever seen something glowing in the dark and wondered how it works? Let me tell you a fun story about when I was 12 years old. I was in a toy store, and suddenly, the lights went out. Everything was dark, except for one thing on the wall that was glowing brightly. I was so amazed that I used my allowance to buy it, and I’ve loved glow-in-the-dark things ever since!
Our friend Sylee has a great question: How do things glow in the dark? It’s a fun mystery to solve! You might have seen glow sticks or glow-in-the-dark stars. They’re different from things like lava or light bulbs, which glow because they’re hot. Glow-in-the-dark items don’t need heat or electricity to shine. So, what’s their secret?
Let’s start with glow sticks. When you first get a glow stick, it doesn’t glow. To make it shine, you need to bend it gently until you hear a snap. This sound is a clue! Inside the glow stick, there are two different liquids. One is inside a tiny container. When you bend the stick, you break the container, and the liquids mix. This mixing is what makes the glow stick light up. Isn’t it amazing?
Now, let’s talk about glow-in-the-dark stars. These stars need light to glow. You have to shine a light on them first. They contain a special material called phosphorescent, which comes from an ancient Greek word for light. This material stores the light and then releases it slowly, making the stars glow in the dark. You can do this over and over again!
Did you know that some living things can glow too? Fireflies have special substances in their bodies that mix together to create light, just like glow sticks. There are also jellyfish that pulse blue light to warn predators, and certain mushrooms in forests that glow. In the ocean, tiny creatures called Sea Sparkles light up when the water moves around them. Nature is full of glowing wonders!
Long ago, people discovered stones near Bologna, Italy, that glowed at night. They thought the stones had magical powers! But now we know these stones are made of phosphorescent material, just like glow-in-the-dark stars. They glow after being in the sunlight all day.
Isn’t it fascinating how different things can glow in the dark? Whether it’s a glow stick, a star, or a firefly, each has its own special way of shining bright. Keep exploring and stay curious about the world around you!
Glow Stick Experiment: With the help of an adult, get a few glow sticks and try bending them to make them glow. Observe what happens when you bend the stick and listen for the snap. Discuss with your friends or family what you think is happening inside the glow stick. Can you think of other things that change when two things mix together?
Glow-in-the-Dark Star Hunt: Find some glow-in-the-dark stars or stickers and place them under a lamp for a few minutes. Then, turn off the lights and see how they glow! Try placing them in different parts of your room and see if they glow differently. Why do you think they need light to glow?
Nature’s Glow Observation: Go on a nature walk with an adult and look for things that might glow in the dark, like fireflies if it’s the right season. If you can’t find any, research with your family about other glowing creatures like jellyfish or mushrooms. Draw a picture of your favorite glowing creature and share what makes it glow!
Sure! Here’s a sanitized version of the transcript:
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Hi, it’s Doug. This is one of my favorite things. When I was about 12 years old, I was visiting a toy store when all of a sudden the power went out. Everything went black, except for this. There it was, hanging on the wall, glowing in the dark. I had to have it. I spent my allowance to get it, and I’ve had it ever since. I still love things that glow in the dark.
Someone named Sylee has a question about things that glow in the dark. Let’s give her a call now.
Hi Doug.
Hi Sylee.
I have a question. How do things glow in the dark?
That’s a great question. Glow-in-the-dark things are so fun to stare at and play with, like these glow sticks that people are wearing or this glow-in-the-dark goo that people are playing with. But maybe part of why we like them so much is that they’re unusual. Most things we see that glow are glowing because they’re hot, like lava or the coils inside a toaster oven. Even the part inside a light bulb glows because it’s hot. But glow-in-the-dark materials, like glow-in-the-dark stars and glow sticks, are different. They don’t glow because they’re hot, and you don’t have to plug them in to anything.
So, how do glow-in-the-dark things work? What is it about them that makes them glow? Before I say anything more, what do you think? Now would be a good time to pause the video and discuss.
Okay, you ready? You might have noticed that the material in glow-in-the-dark stars acts differently than the stuff inside glow sticks. There are different ways these two things work. With glow-in-the-dark stars, first, you have to shine a light on them to get them to glow. That’s not true with glow sticks. If you’ve ever seen a glow stick when you first buy it, it’s not glowing. To get the glow stick to start glowing, you have to gently bend it.
Listen. (snap) You hear that snapping sound? That’s actually a clue about what’s happening inside a glow stick. Inside a glow stick are two different liquids. One substance is floating around inside the stick, while the other is in a container located inside the stick. When you gently bend the glow stick to get it started, you’re breaking that small container open, causing the two substances to mix together. Mixing the two substances together is what makes the glow stick glow.
It’s amazing that mixing two substances together can create something that glows. Around a hundred years ago, scientists discovered how to make these substances in a laboratory. There are actually a few different substances that can do this, each glowing different colors, like red, yellow, and so on. We call these luminescent substances, from the ancient Roman word “lumen,” which means light.
Scientists figured out that the reason fireflies glow is because they have these substances inside their bodies that they can mix together. So fireflies glow for similar reasons as glow sticks. They both contain special substances that glow when mixed together. And it’s not just fireflies either. This is the underside of a jellyfish that pulses blue light to warn its predators. Even some living things other than animals can do this, like certain mushrooms found in many forests in Asia. There’s even a type of mushroom in North America called the Jack-o’-lantern that glows on its underside.
But maybe the most spectacular of all are tiny microscopic organisms found in the ocean that sometimes wash up on shore. They’re called Sea Sparkles, and they glow when the water around them gets disturbed. Isn’t this amazing? Look as this person runs their hands through the water.
So all of these living things glow for similar reasons as a glow stick. But what about glow-in-the-dark stars? I mentioned before that glow-in-the-dark stars only glow once you shine light on them. Like glow sticks, they contain a special kind of material that’s been prepared in a laboratory. Because this material doesn’t work exactly like the stuff in glow sticks, scientists give it a different name: phosphorescent, from the ancient Greek word for light.
Phosphorescent materials store the light that you shine on them and then release that light very slowly. Unlike glow sticks, you can do it again and again. There are very few materials like this found in nature. One of the greatest mysteries of science was the discovery of the Bologna stones, found near a mountain in Bologna, Italy. Each night after the sun goes down, the Bologna stones start to glow, but only if the sun had shone on them all day.
At first, it was thought that these stones might have some kind of magical powers. But today, we know that the Bologna stones are just stones made of a phosphorescent material, similar to what scientists later invented for glow-in-the-dark stars. This material may not make you rich, and it won’t make you live forever, but it is fun to look at.
That’s all for this week’s question. Thanks, Sylee, for asking it. Now for the next episode, I reached into my question jar and picked three questions submitted to me that I’m thinking about answering. When this video is done playing, you’ll get to vote on one. You can choose from: “When were shoes invented?”, “Why do we sneeze?”, or “Why can’t fish breathe on land?”. So submit your vote when the video is over. I want to hear from all of you watching. There are mysteries all around us. Stay curious and see you next week.
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This version removes any unnecessary informalities and maintains a clear and informative tone.
