The contrail would normally appear white, but the large volume of air toward the setting Sun preferentially knocks away blue light, giving the reflected trail a bright orange hue.

• 这条飞行云在正常情况下呈白色，但朝向落日方向的大量空气优先反射蓝光，使得这条空气轨迹呈现了明亮的橘红色。