David Gifford Photography

Noctilucent Clouds, Lerwick

Rare noctilucent (“night-shining”) clouds photographed in the night sky looking north from Lerwick.

Reading-up about noctilucent clouds, I found some interesting facts on the Royal Museum Greenwich and the Met Office websites:

  • Noctilucent clouds are the highest clouds in our atmosphere, forming in the mesosphere, a layer of the atmosphere that is around 80 kilometers (50 miles) above Earth’s surface.

  • They glow with a blue or silvery hue at night when illuminated by sunlight from below the horizon.

  • They’re only seen at high latitudes, between 45°N and 80°N in the northern hemisphere, and equivalent latitudes in the southern hemisphere.

  • They’re made of ice crystals formed on dust particles. Sources of dust include micro-meteorites and volcanic eruptions, as well as man-made pollutants.

  • Noctilucent clouds are thought to be increasing in number and brightness, which may be due to climate change.

Image #1297