Why Is the Sky Blue? | Easy Science Reading

 

This short science reading passage is for English learners. Read the passage, learn key vocabulary, and answer the questions.

The sky looks blue because air scatters blue light from the sun.

Reading Level

A2-B1

Word Count

284 words

Reading Passage

On a clear day, the sky often looks bright blue. But the sky is not painted blue. The color comes from sunlight and the air around Earth.

Sunlight may look white, but it is made of many colors. These colors include red, orange, yellow, green, blue, and violet. When sunlight reaches Earth, it travels through the atmosphere.

The atmosphere is full of tiny gas molecules and small particles. When sunlight hits these tiny things, the light spreads in different directions. This spreading is called scattering.

Blue light scatters more easily than red or yellow light. This is because blue light travels in shorter waves. When blue light scatters through the air, it comes to our eyes from many parts of the sky. That is why the sky looks blue during the day.

At sunrise and sunset, the sky can look orange, pink, or red. This happens because sunlight travels through more air when the sun is low. Much of the blue light scatters away before it reaches our eyes. The warmer colors can travel farther, so we see them near the horizon.

The sky may also look gray on cloudy days. Clouds are made of tiny water drops. These drops scatter many colors together, so clouds often look white or gray.

The blue sky is a simple but beautiful sign of how light and air work together. Every clear day gives us a science lesson above our heads.

Sunlight has many colors, but air scatters blue light more strongly.

Key Vocabulary

Word	Meaning	Example
atmosphere	the layer of air around Earth	Sunlight travels through the atmosphere.
scattering	light moving away in many directions after hitting something	Scattering helps make the sky look blue.
molecules	very tiny pieces that make up air and other things	Air molecules scatter sunlight.
horizon	the line where the sky seems to meet the land or sea	The sunset looked red near the horizon.
cloudy	covered with many clouds	The sky looks gray on a cloudy day.

Reading Comprehension Questions

1. What colors are in sunlight?
2. What is the atmosphere?
3. Why does blue light scatter more easily?
4. Why can the sky look red or orange at sunset?
5. Why do clouds often look white or gray?

Answers

1. Sunlight is made of many colors, such as red, orange, yellow, green, blue, and violet.
2. The atmosphere is the layer of air around Earth.
3. Blue light scatters more easily because it travels in shorter waves.
4. At sunset, sunlight travels through more air, and warmer colors can travel farther.
5. Clouds scatter many colors together, so they often look white or gray.

Short Summary

The sky looks blue because sunlight passes through Earth's atmosphere. Tiny air molecules scatter blue light more than other colors, so blue light reaches our eyes from many directions.

More Easy Readings

• How Are Rainbows Made?
• What Is the Water Cycle?