The blue sky


B: Joe asked me something about science just now. But I didn’t know the answer.

G: I’m good at science. Ask me.

B: OK. Why is the sky blue?

G: I’ll explain it in a simple way. Light comes through the air from the sun in waves.

B: The light is in many colors, right?

G: Right. Blue light waves are smaller than air molecules. They sometimes get absorbed by these molecules.

B: OK. What happens then?

G: Then the blue light waves scatter in many directions. Your eyes see this blue light from above you, after it leaves the air molecules.

B: So that is what makes the sky blue! What happens to the other colors?

G: They reflect off the things that they hit. Your shirt is red because our eyes see the red light reflected from it.

B: Now I understand why the sky is blue!


  • wave /weɪv/: sóng (sóng biến, sóng âm…)
  • molecule /ˈmɑː.lɪ.kjuːl/: phân tử
  • absorbed /əbˈzɔːrbd/: hấp thụ
  • scatter /ˈskætər/: tiêu tan, tan biến, biến mất
  • reflect /rɪˈflekt/: phản chiếu