On the nights of the 12-13 and 13-14 of July, 2016, Denmark has witnessed two very powerful and bright noctilucent cloud shows in a row. The brightest and broadest I can remember to date anyway.
Noctilucent clouds are a beautiful seasonal phenomenon. The clouds appear at night and shine silver-blue. They sometimes light up summer night skies at high latitudes – say, about 45 degrees N. or S. – from May through August in the Northern Hemisphere and from November through February in the Southern Hemisphere. These clouds form in the highest reaches of the atmosphere – the mesosphere – as much as 50 miles (80 km) above the Earth’s surface. You can see in the video above that ordinary clouds are scuttling below them …
Noctilucent clouds are thought to be made of ice crystals that form on fine dust particles from meteors. They can only form when temperatures are incredibly low and when there’s water available to form ice crystals.
Thank you, Adrien!
Bottom line: Time-lapse video of July 12-14, 2016 noctilucent cloud display over northern Europe.
Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.