Why Do Some Things Glow in The Dark? - Parenting with Natacha

Children are fascinated by things that glow, especially in the dark! The question you will invariably get asked is: How does it glow in the dark? Here is a simple explanation you can share with your young child:

Things that glow in the dark contain a substance called phosphor. Phosphor can radiate light after it has become energized. To become energized, they soak up light energy for a long time, and then they radiate light in the dark.

Very simply put phosphors “store up” light energy and then radiate it.

What Is Luminescence?

It is a process that occurs when a substance emits light without heat. It does not have to “glow in the dark”, it just has to give off light by itself. This is different than the light we get when we burn things (like wood for example) – this type of light results from the heat. There are a few different types of luminescence, including phosphorescence and bioluminescence.

Fluorescent substances absorb ultraviolet light and then glow when they re-emit it.

Phosphorescent things have phosphors, and they make light the same way as fluorescent things do, but they can glow for a longer period of time after the light is gone.

All things that glow in the dark have phosphors. There are many different kinds of phosphors.

Some living things and even objects, glow when we shine a black light on them. When the light waves of a black light hit an object that contains phosphors, it will naturally fluoresce (glow).Did you know that some plants or animals are also luminescent? They use a chemical process called bioluminescence. They have a special enzyme that convert stored energy into light (without creating heat) which makes them bioluminescent. Here are some animals you may recognize:

A note from Natacha: Parents, please watch the video first without your child and decide whether it is appropriate to watch with them. You may want to watch some on mute, and discuss with your child what they are seeing instead. I provided some links to videos so children can see how these animals are and act, which is much more information than seeing a picture only, but I did not make these videos and therefore am not responsible for their content. Use your discretion.

Fireflies