UV beads reveal the benefit of sunscreen
Discovery Place Science
Although it is the middle of winter, we are already thinking about summer – green grass, cool pools, camps and, of course, lots and lots of sun.
The sun is amazing for so many reasons. The sun is a huge star. It is 109 times larger than the Earth! As the center of our solar system, the sun primarily consists of hydrogen and helium. It is basically a big ball of gas. Despite being able to see the sun and feel the heat from the sun, it is very far away – 92.96 million miles from the Earth to be exact.
Aside from warm weather, the sun provides a lot of other things for us:
- The suns UV light is used by plants to make food. We, in turn, eat some of those plants. Both plants and animals could not survive without each other or the sun.
- Humans use sunlight to create vitamin D. When we are exposed to sunlight, our skin reacts to cholesterol in our skin cells and allows the vitamin D to be made. These nutrients are needed to keep bones, teeth and muscles healthy.
- Without the warmth from the sun, the earth would freeze.
Humans benefit from the sun’s rays but too much sun can cause some problems. If you get too much sun, you can get what is called a sunburn. When going out in the sun it is important to protect ourselves. We can do this by wearing a hat or sunglasses, wearing long-sleeved shirts and sunscreen.
Sunscreen is made to protect our skin by blocking UV rays. Some varieties use chemicals to absorb the rays and others make a barrier to shield us from the rays.
We can demonstrate how this works with these special UV beads, which react to UV light:
They turn from plain white to purple when you put them in the sun or shine a UV light on them.
Here, you can see that we have two containers with beads in them. One we are going to leave as is and the other we are going to cover in sunblock.
Now we are going to place them in direct sunlight. The beads without sunblock have changed color but the ones with the sunblock are still white. Pretty neat!
You can buy your own UV beads and test this out at home if you want. Be sure to keep this experiment in mind the next time you spend time outdoors. Whether it is winter or summer, stay sun smart by protecting your skin while enjoying the sun’s awesome rays!