Rainbows

Rainbows. Written by Sean McCollum. Focus question. How does a rainbow form?

《彩虹》 作者：肖恩·麦科勒姆 核心问题 彩虹是怎么形成的？

Introduction. When the sun shines after it rains, run outside. You may see a giant rainbow sweeping across the sky. Sometimes you may even spot small rainbows indoors when sunlight shines through a window.

引言 雨后出太阳的时候，快跑到外面去吧。 你说不定能看到一道巨大的彩虹横跨天空。 有时候阳光透过窗户照进来，你甚至能在室内看到小小的彩虹哦。

Rainbows are illusions made by light. We can see them, but we can't touch them or walk around them. Outdoor rainbows seem to move away when we go toward them. Rainbows appear when light shines through something clear, like water. They are beautiful tricks of light. Science, though, can explain the tricks.

彩虹是光制造出来的幻象。 我们能看见它们，却摸不到，也没法绕到它们身后。 我们朝着户外的彩虹走过去时，它好像会往远处退。 当光穿过水这类透明的东西时，彩虹就会出现啦。 它们是光玩的美丽小把戏。 不过科学能解释这些小把戏哦。

where and when rainbows appear. Look around the next time you see a rainbow. The sun will be shining from behind you, and there will be rain in front of you. That is where you will see the rainbow.

彩虹出现的时间和地点 下次你看到彩虹的时候，四处看看。 太阳会在你身后照着， 而你的前方会有雨。 你就是在这样的情况下看到彩虹的哦。

Rainbows need water drops and sunshine to form. Rainbows most often appear in the morning or late afternoon. That's when the sun is in the best places to create one. You might even see a double rainbow.

彩虹的形成需要水滴和阳光。 彩虹最常出现在早晨或者傍晚。 这时候太阳的位置最适合形成彩虹。 你说不定还能看到双层彩虹哦。

You may see rainbows in the midst of a waterfall, too. A splashing fountain can also create a small rainbow. Rainbows can even form under a bright moon. These are called moonbows.

你也可能在瀑布中间看到彩虹。 溅着水花的喷泉也能造出小小的彩虹。 明亮的月亮底下也能形成彩虹哦。 这种彩虹叫做月虹。