Month: January 2012

Welcome to the January 27, 2012 edition of STEM Friday.

Are you looking for Science, Technology, Engineering or Math children’s books? Then you’ve come to the right place. We’ve gathered some of our recent  favorites to share.

For my contribution, I am featuring a book that would be an excellent tool for a discussion on the pros and cons of advancements in technology. Becoming Invisible: From Camouflage to Cloaks by Carla Mooney is a detailed look at what is happening in the high tech world of cloaking.

Camouflage and invisibility are fascinating topics. Everyone who has read the Harry Potter books probably wished they could have an invisibility cloak, too. Can you imagine how much fun it would be to be able to hide in plain sight?

Mooney explains the differences between camouflage and invisibility. With camouflage, the colors and patterns help the wearer blend in with the environment, but you can still see them if you know where to look. The idea of camouflage was proposed by an artist who studied the markings of animals in the late 1800’s. During World War I, the armies and navies of many countries tested camouflage patterns to hide both equipment and people, leading to the camouflage uniforms used by military personnel today.

“Optical camouflage” is another form of camouflage which uses projectors to display scenes of the moving background onto special reflective cloaks. From the right angle, it is impossible to tell where the cloaked person (or object) is standing because he or she seems to be part of the background images. If the viewer isn’t in line with the projectors, however, the illusion doesn’t work.

On the other hand, when something is truly invisible, our eyes can not see it. To attempt to produce true invisibility, scientists have trying to bend light to go around objects. Researchers have been able to bend types electromagnetic waves that are near relatives of visible light with special man-made materials called metamaterials. Using metamaterials made of metal and fiberglass, scientists have been able to develop “cloaks” that bend either microwaves or infrared light around an object, hiding it from detection. Both microwaves and infrared radiation have longer wavelengths than visible light, so the metamaterials will have to get smaller to be able to bend visible light. The possibility, however, seems more likely than ever before.

In Chapter 4, Mooney gives some ideas how invisibility cloaks could change the world if engineers and scientists succeed. She suggests several positive uses for the technology, but points out that it could be dangerous, as well. Can you imagine if criminals could become invisible? What about if enemy armies could cloak themselves and then suddenly appear well inside our borders? Other worry that invisible agents could spy on our every move without our knowledge or consent.

Becoming Invisible: From Camouflage to Cloaks gives the reader a lot to think about. I definitely recommend it to students who are considering physics or engineering as careers.

Be sure to check out the Camouflage and invisibility activities at Growing With Science that were inspired by the book.

Today’s STEM Friday recommended books:

(Links take you to the review of each title.)

	Jeff at NC Teacher Stuff has Open Wide! by Catherine Ham
	Shirley at Simply Science has the lovely A Leaf Can Be… by Laura Purdie Salas
	Precious at Rourke Publishing Blog highlights Fossils, Uncovering the Past by Tom Greve
	Anastasia has Freaky-Strange Buildings by Michael Sandler at Booktalking.

If you would like to participate in STEM Friday in the future, go to Booktalking blog and click on STEM Friday for more information.