Science 3032 Colors in the Sky

Science 3032 Colors in the Sky
What makes rainbows form, and when can you see them?
Next time you see the sun come out during or just after a rain, look outside. This is the perfect time to spot a rainbow. Many cultures have stories that explain how rainbows form in the sky. Today, we know that rays of light pass through drops of water create rainbows.
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Sunlight is actually made of different colors. When a ray of sun enters a raindrop, it refracts, or bends slightly. Each different color bends at a slightly different angle so they separate out. The light also bounces of the back of the water drop. This is called reflection. When light bends and bounces through thousands of raindrops, you see a rainbow in the sky. A rainbow contains the colors of the spectrum.
The main colors of the rainbow appear in the same order: red, orange, yellow, green, blue, indigo, and violet. Some people remember the order using the initials in the name ROY G. BIV. It’s rare, but sometimes you can see a double rainbow. The colors in the outer, dimmer rainbow are the opposite of a regular rainbow—violet comes first, and red appears last.
A prism is a piece of glass that is used to split light into its colors. Isaac Newton was the first scientist to figure out that a prism could separate light into colors. Before that, people had thought that the prism made the colors. They didn’t realize that all the prism did was make the colors in light visible.
Using a prism is an easy way to make a rainbow at home. Try shining a flashlight through a prism onto a sheet of white paper. The light changes speed as it enters the prism. It bends and reflects onto the paper as the colors of the spectrum.


甚麼時候是看見彩虹的完美時機?下次當太陽出現於下雨時或下雨後，你只要往外一看便可以看到彩虹。陽光其實是由數種顏色的光所組成的，只要使他穿過例如水滴或三稜鏡使他在其中轉折分散便會形成如彩虹一般多重的顏色。