Sources of Light

Near the beginning of this unit we went through a general overview of different sources of light.

Besides the sun and fire, there's chemoluminescence, fluorescence, and bioluminescence. Glowsticks use chemoluminescence by mixing two reactive chemicals that release energy when combined. There is a good explanation here:

How glow sticks work

And a video on how you can make your own glowsticks, here. You have to have specialized chemicals and it's not super easy to make them, so it's not something we wanted to try, but the video is still interesting.

When we examined the glowsticks closely, we could see the small inner container which breaks when you bend the glowstick to activate it.

Here are some interesting videos about bioluminescence:

Animated video showing different animals that bioluminesce (good except that the narrator has a strange fixation with talking about "raves," for some reason)

This one is really short and you'll want to turn down the sound to avoid the swearing. But it's cool to see algae suddenly light up blue when the water is disturbed.

This video shows someone swimming among the bioluminescent dinoflagellates—gives a better idea of how huge some of these masses are

And, since none of us have ever seen fireflies in real life, we watched this video showing what they look like (there were some in Utah a couple years ago!)

This page has a good diagram showing one way atoms make light (fluorescence), along with a good overview of what light is.

And here's an explanation of how "black lights" work.