彩虹通常出现在雨过天晴的时候，当空气中残有微小水滴时，太阳照射析出彩色光芒，形成彩虹。同时，如果条件具备，霓随之也会出现。本期视频会讲解彩虹形成的原理及观测彩虹的经验，让您不会错过彩虹！

Rainbows usually appear when the sky is clear after a rain. When tiny drops of water remain in the air, the sun shines a colorful light, forming a rainbow.At the same time, if the conditions are right, the secondary will also appear.This video explains how rainbows form and how to observe them, so you won't miss a rainbow!