Rainbows, such as this one produced by artificial light shone on an icy Niagara Falls, are just one special effect of light, a marvel that reveals the world to us.

• 彩虹，例如这幅图片制作被人工的灯光照耀在一个结冰的尼亚加拉瀑布上，正好是一种特别的光亮，一个罕见的例子显露在我们的世界。