"Everything Emits Infrared Energy - Even You!" Activity
(For a smaller group)
4-6 infrared thermometers*, with a 20" cord attached to each
Low-adhesive tape (such as painter's tape)
Desk lamp with incandescent bulb (inexpensive one is fine)
Blocks of blue ice; put in freezer the night before use (Use one with the display and save the other, wrapped up to keep it cold. When the first block warms up after a few hours, trade it for the colder second block.)
Block of wood
Hand warmer (disposable packet version)
Small LED lamp
1. Display the electromagnetic spectrum poster on an easel near the table where you set up this activity.
2. Plug the desk lamp in (use the extension cord if needed). Set the lamp near the back of the activity table so young hands can't grab it and get burned. Put a small "Do not touch" sign on the lamp.
3. Tape the free end of each cord under the edge of the table where the children will stand. Space them apart about 6".
4. Place the other items on the table. Briefly explain to the children that everything emits infrared energy (with older students, use the word "radiation"). It's a kind of energy our eyes aren't designed to see, but this is the kind of energy the Webb telescope will be able to see. Explain that infrared energy allows us to see objects such as stars that are hidden by gas and dust in space; the infrared energy waves those objects emit can penetrate through the gas and dust, even though the visible energy waves can't.
5. Model for the kids using one of the thermometers. Remind them that they do not need to touch the thermometer to the objects because every object is releasing its own infrared energy. They should hold the thermometer about the same distance from each object.
Tell them that humans' eyes aren't able to see infrared energy, but we can detect it by objects' temperature. Have them compare the temperatures. Prompt them to check their own temperatures, and that of their parents or friends.
Briefly point out infrared waves on the electromagnetic spectrum poster, and where visible waves exist on the spectrum.
*The infrared thermometers were from Amazon.com (Kintrex IRT0401 Compact Waterproof (IP67) Infrared Thermometer ) and they were $19.95 each. Six were ordered, and shipping was free.