Discuss the concept of light travelling, shadow and refraction. Ask the children to draw and annotate a diagram of how a shadow is formed. Then watch the following videos: ...

Watch this video which explains how light travels into our eyes so that we can see things. Of course, you can only see something when there's light. And what is light? It's energy that zooms ...

Although they travel at the fastest possible speed (the ... In metric units, that's about 300,000 kilometers per second. How long does light take to reach us from familiar objects?

A series of new animations by a NASA scientist show just how zippy — and also how torturously slow — the speed of light can be. Light speed is the fastest that any material object can travel ...