Light

Light is a kind of energy that our eyes can see. The sun gives us most of our light during the day. Light bulbs, fires, and screens also make light. Light travels in straight lines very, very fast. Without light, everything would be dark.

How Light Works

Light comes from things that glow, like the sun or a lamp. When light hits an object, some of it bounces off. This bouncing light goes to our eyes, and that is how we see. Things that let light pass through, like glass, are called transparent. Things that block light make shadows.

The Speed of Light

Light is the fastest thing in the universe. It moves about 186,000 miles each second. Light from the sun takes about eight minutes to reach Earth. Light from far away stars can take many years to get here. Nothing we know of can go faster than light.

Fun Facts

• White light is actually made of many colors mixed together.
• A rainbow forms when sunlight shines through tiny drops of water.
• Some animals, like fireflies, can make their own light.

Did You Know?

The light from some stars you see at night left those stars thousands of years ago.