Noctilucent Clouds:
Rare noctilucent clouds that form in summer high up in the Earth’s atmosphere have been recently seen from parts of Scotland.They are thin, wispy clouds that glow with a blue or silvery hue at night when illuminated by sunlight from below the horizon. Horizon refers to the apparent line that separates the Earth from the sky—specifically, the point below which the Sun appears to set. The name ‘noctilucent’ is derived from the Latin words “nocto” and “lucent” which translates to “night” and “shining” respectively. They are sometimes referred to as polar mesospheric clouds. Most of our planet’s clouds form in the Earth’s troposphere. Noctilucent clouds are located in the third layer of Earth’s atmosphere, the mesosphere, making them Earth’s highest clouds.
