Space Radiation - UV Man
Children use common craft materials and ultraviolet (UV)-sensitive beads to construct a person (or dog or imaginary creature): UV Man! They use sunscreen, foil, paper, and more to test materials that might protect UV Man — and ourselves! — from being exposed to too much UV radiation.
Families or other mixed-age groups, including children as young as 4 years old with assistance from an older child, teen, or adult
School-aged children ages 5–7 and 8–9
Tweens up to about age 13
What's the Point?
- Ultraviolet radiation comes from our Sun
- While some UV radiation is necessary, too much can harm humans (and other living organisms)
- Engineers and scientists work to keep astronauts safe from UV radiation in space — just like we must protect ourselves from harmful UV radiation here on Earth!
For the Facilitator
For Each Group of 10–15 Children
- 30–45 UV beads (available in craft stores as well as through online retailers such as Educational Innovations and Steve Spangler Science)
- 20–30 non-UV pony beads
- 20–30 chenille sticks, preferably white
- 3 or more pairs of scissors
- Various common materials to test for “protecting” UV Man from UV radiation, such as:
- 15 or more sheets of construction paper (in various colors)
- 15 or more sheets of copy paper (preferably reused)
- 1 roll of aluminum foil
- 1 roll of plastic wrap (in various colors)
- 5 pairs of paper sunglasses (may be obtained from an optometrist)
- 1 (1 oz.) bottle of sunscreen, SPF 30
- 1 (1 oz.) bottle of sunscreen, SPF 50
- 1 roll of masking tape
- 10 or more strips of cloth
- Optional: containers of water
NASA’s Spot The Station
As the third-brightest object in the sky, the International Space Station is easy to see if you know when to look up. Use NASA’s Spot The Station service to find upcoming sighting opportunities for several thousand locations worldwide. Plus, sign up to receive notices of opportunities via e-mail or text message!
International Space Station
Find information about the space station, its international crew, and how they live and work in space.
Tour of the Electromagnetic Spectrum
Explore the amazing world beyond the visible! Text and images introduce electromagnetic waves, where they come from, how they behave, and how scientists use them. In addition to the website, a book is available for download as a PDF, and there is a companion video. Appropriate for ages 12 and up.
Six months before the activity
- Prepare and distribute publicity materials for programs based on this activity. If possible, build on the children’s knowledge by offering multiple science, technology, engineering, art, and mathematics (STEAM) programs.
- Review the Facilitator Background Information.
- Plan for any introductory activities or extensions that you’d like to incorporate with this activity. Consider using an “icebreaker” activity to help the children get to know each other.
- For young children, plan to provide assistance with cutting and threading the beads on the chenille sticks. Consider allowing extra time for this activity for young children.
- Create a UV Man to serve as an example for the children to follow.
The day before the activity
- Place the example UV Man where everyone can access it.
- Arrange the materials on the tables so that participants can access them.
A child at Sterling Municipal Library (Baytown, Texas) created a UV Man using beads and chenille sticks. Later in the program, she took her creation outdoors to observe that the special “UV beads” change colors when exposed to UV radiation in direct sunlight and even in shade!
Credit: Sterling Municipal Library and the Lunar and Planetary Institute.
|The UV-sensitive beads used in this activity serve as UV radiation detectors. They change color when exposed to UV radiation from the Sun or from UV lights. The brightness of the color corresponds to the intensity of the UV radiation. When shielded from UV sources, or when exposed to light that does not contain UV radiation — such as indoor light bulbs — the beads remain white. The beads are designed for multiple use and, according to the manufacturers, will change color up to 50,000 times.
1. Share ideas and knowledge.
- Introduce yourself. Help the children learn each other’s names (if they don’t know each other already).
- Frame the activity with the main message: Engineers work to keep astronauts safe from UV radiation in space — just like we must protect ourselves from harmful UV radiation here on Earth!
Humans need UV radiation because our skin uses it to manufacture vitamin D — vital for maintaining healthy bones. About 10 minutes of Sun each day allows our skin to make the recommended amount. However, too much UV exposure causes the skin to burn and leads to wrinkled and patchy skin, skin cancer, and cataracts.
On Earth, we are protected by our atmosphere from most UV radiation coming from the Sun. The ozone layer absorbs much of the UV, but some still gets through. We can protect ourselves by covering with clothing and using sunscreen.
In space there is no atmosphere to protect astronauts from UV radiation. Astronauts have to provide their own protection in the form of space suits, helmets with protective visors, and space stations. While these measures work very well for protecting against UV radiation, the higher-energy radiation is not completely blocked. Even with protective shielding, astronauts onboard the International Space Station receive a daily dosage of radiation about equal to eight chest X-rays! Astronauts wear special radiation detectors — dosimeters — that help determine how much exposure they have had to radiation.
- Invite the children to talk about what they already know about UV radiation, what they’ve experienced at home, and how they protect themselves in their daily lives. Use open-ended questions and invite the children to talk with you and each other.
|Use discussion to help them start to think about prior experiences and build new understandings about UV radiation and ways to protect ourselves from it, both on Earth and in space. Some conversation-starters are:
For older children, guide the conversation toward identifying the Sun as the source of UV energy or radiation. Clarify that this energy is invisible to our eyes and we cannot feel it, but it still affects our bodies. As necessary, explain that Earth’s atmosphere blocks much of the Sun’s UV light. The ozone layer in our upper atmosphere forms a protective sphere, absorbing much of the UV energy.
2. Guide the children in each creating a person or creature with a built-in UV-radiation “detector.” Explain that they will incorporate UV beads, which are made from a special pigment that is very sensitive and turns colors when exposed to UV rays. With the help of UV Man, they will investigate the source of UV radiation and how we can best protect UV Man — and ourselves! — from it. Have the children follow these steps to create a UV Man (and make their own variations, if they’d like!):
- Cut two pipe cleaners in half.
- Fold one piece in half; these will be his legs.
- Connect a second piece to the legs to make his torso.
- Thread the beads onto his torso, alternating UV with non-UV beads. Slide all the beads toward UV Man’s legs.
- Twist the third piece around the torso above the beads to make arms.
- Form a circle with the last piece and use it for his head.
3. Observe UV Man’s UV radiation detectors (i.e., the UV beads) indoors, in shade, and finally, in full sunlight. Encourage the participants to discuss their predictions first, then their observations, with each other and with you. Be thoughtful about your approach and keep the UV beads covered when walking outside to a shady spot. After making observations, “reset” the beads by covering them for about one minute and have a discussion to predict what will happen in full sunlight. After moving to full sunlight, continue making observations and discussing possible explanations for those observations. Once indoors, continue making observations about the beads’ appearance and discussing possible explanations for those observations.
|The color of the UV beads remain white or creamy indoors. In shade, the UV beads become lightly colored, indicating that, even in the shade, there is some UV radiation reaching the detectors and our skin. In full sunlight, the UV beads become deeply colored, reacting to the intensity of the UV radiation to which they are being exposed.
Allow the children’s thinking to be shaped by the experience — refrain from giving any of your own conclusions or expectations. Encourage them to talk to each other (in pairs or small groups) as they note their observations and form predictions about how the UV beads will change in the different settings. Ask questions to help them explain their conclusions, e.g., that the UV beads become brightly colored in full sunlight because UV radiation from the Sun is falling on them. Some children may say light caused them to change, and others may say heat. Remind them of their observations about the beads inside; the beads were white, even though they were in the light of the room. Ask them what happened to their beads when they brought them back inside; the beads changed from a colored state in the Sun back to white in the room light. Visible light does not affect the beads. If it is suggested that heat causes the change, invite the children to hold beads in their fists; the beads do not change color when heated. They can also heat the beads with a hair dryer. The cause of the change comes from the Sun; it is from the part of the Sun’s spectrum we do not see or feel directly.
4. Test two materials to see if they protect UV Man from UV radiation. Generate ideas for how the children might prevent the beads from changing again in full sunlight. Use everyday experiences, such as wearing clothing, using sunscreen, using umbrellas, or staying inside, to consider how UV Man — and astronauts in space — can similarly protect themselves. Invite the children to thoughtfully test different materials:
- Make a construction paper poncho or shirt to cover the top UV bead.
- Select two additional materials and use them to cover other UV beads.
- Take UV Man into full sunlight and observe how the UV beads do or do not change.
- In pairs or small groups, discuss ideas for why some materials protect UV Man better than others and share those ideas with the whole group.
5. Conclude. Summarize that we encounter UV radiation every day from sunlight. While some UV radiation is necessary for our health, too much can harm humans (and other living organisms). Overexposure to UV radiation causes the skin to burn, sometimes badly (ouch!!). Extreme or excessive burning of the skin can lead to skin cancer. Engineers and scientists test materials — just like the children did — to find ways to keep astronauts safe from UV radiation in space. On Earth, we can protect ourselves from harmful UV radiation by wearing protective clothing, using sunscreen, not staying out in the Sun for extended periods, and not expecting the shade to protect us. Challenge the group to continue testing UV Man’s protective materials in other settings, such as inside a car or outdoors on cloudy days.
Challenge the participants to use craft items to construct and decorate a space capsule for UV Man! Offer a variety of building materials, such as:
- Miscellaneous craft and everyday items: Straws, aluminum foil, plastic wrap (of all colors), old CDs, pipe cleaners, toothpicks, wire, wire cutters, Legos®, construction paper (variety of colors, including black), tinsel, ribbon, fabric, gauze, wood dowels/skewers, rubber bands, shiny streamers, etc.
- For spacecraft body: Pint-sized milk containers, coffee cans, soup cans (tape all sharp edges), disposable cups, empty (clean) Play-Doh® containers, black plastic or biodegradable seedling (plant) trays, paper towel tubes, empty egg cartons, cereal boxes, 2-liter soda bottles, different-sized Styrofoam blocks, other empty plastic or cardboard containers/boxes, etc.
- Other: Use your imagination and best judgment for providing safe, fun, and readily available materials!
Offer illustrations of the engineering design process (The Works or Design Squad are good options), and encourage the participants to iteratively test and change their designs — just like professional engineers do!
January 21, 2015