Also called the Northern Lights, the Aurora Borealis is caused by the solar wind (plasma released from the sun) hit the Earth’s atmosphere. It can only be seen at night because it is not very bright compared to the sun. They have been seen on other planets as well, such as Jupiter and Saturn.
北極光とも呼ばれるオーロラは、太陽風（太陽から放たれるプラズマ）が地球の大気圏に衝突して発生します。太陽ほど明るくないので夜にしか見えません。木星や土星でも、オーロラを見ることができます。
