A Wonderleaf question
Why do things glow in the dark?
a real page from the book
Things glow in the dark when special materials take in light first and give that energy back later as visible light. In phosphorescent paint or plastic, electrons are lifted into higher-energy positions, then return slowly. Each tiny drop sends out a photon.
That is why a sticker fades, then brightens again after time near a lamp. Newer glow powders such as strontium aluminate can shine longer than older mixtures. Fireflies and snap-and-shake glow sticks are doing another job: making light through chemistry instead of stored shine.
Wonder words
- photon
- electron
- phosphorescence
- fluorescent
Try it out
Place a toy near a lamp, switch off the light, and notice which parts reflect light and which actually glow.
Read the whole picture book
Watercolour scenes, straight answers, about three minutes cover to cover.
Open the picture bookKeep wondering
One more wonder: Why is space so dark?
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