Children ages 8–13 investigate how Earth’s atmosphere protects UV Man! — and us! — from harmful ultraviolet radiation in this 60 minute activity. They continue the investigation with UV Man! in space, to determine what will happen to him without the protective blanket of Earth’s atmosphere, and create a capsule to protect him.
For each group of 4 to 5 children:
For each child:
1. Introduce the concept that the Earth’s atmosphere protects us from ultraviolet radiation.
2. Invite the children to take turns placing their UV Men on a table or the ground, and then hold the atmospheric blanket (cotton fluff) about six inches over him. Ask them:
3. Have them hold the spray bottle about 6 inches from the atmosphere and spray 5 or 6 times. Invite their observations.
4. Invite the children to uncover UV Man!
5. Have them experiment by taking UV Man! up beyond the cotton fluff atmosphere. Have one child in each group hold UV Man! at arm’s length and have another child hold the spray bottle about 6 inches from UV Man! and spray him 5 or 6 times.
6. Invite the children to reassemble as one large group. Ask them what they observed when UV Man! traveled in space.
Explain that Earth’s atmosphere protects us from many of the dangerous types of radiation from our Sun – ultraviolet, X-rays, gamma-rays, and very high energy cosmic rays. We know that some ultraviolet radiation still gets through, but we can protect ourselves by covering up, limiting our time in the Sun, and using sunscreen.
Astronauts, however, live and work above Earth’s atmosphere, so they could be exposed to very dangerous levels of ultraviolet radiation – and other types of radiation traveling from our Sun and from elsewhere in our galaxy and universe. They, too, must take precautions. They work in spacecraft that have special shielding, wear special suits when they work outside of the spaceship, and even have special visors to protect their eyes. Even with all of this protection, some high energy radiation can still pass through the shielding. Astronauts wear instruments, called dosimeters, that monitor how much radiation each of them has received. Once they reach certain levels, they do not continue to work in space.
And just like the children worked hard to find which materials would protect UV Man! from ultraviolet radiation — and some protected him better than others — NASA tests all sorts of materials and coatings for spacecraft and space suits to protect the astronauts.
7. Invite the children to use the craft items to construct a spaceship for their UV Man! When they have finished, have them spray the spaceship a few times to see if it successfully blocks "radiation".
Invite the group to share what they have learned about ultraviolet radiation on Earth and in space. What helps protect Earth from most of its harmful effects? How is ultraviolet radiation a challenge to astronauts? What do you think are some ways for astronauts to protect themselves from UV radiation? What happens to astronauts — and kids — who receive too much UV radiation?
