There have been these relatively rare clouds on a couple of previous nights now.
Last night I managed to get to the nearby lake and took some photos of this interesting phenomena.
Noctilucent clouds are much higher (about 80km high) than normal clouds and they are composed of tiny crystals of water ice in addition to dust particles. Source of these are not known for certain.
I searched some info about these clouds on Wikipedia and seems that possible sources are micrometeors, volcanoes and dust from troposphere. Also reaction of methane with hydroxyl radical could be the source.
First records of these clouds have been made on year 1885 which is two years after the 1883 eruption of Krakatoa. Much more info can be found from
Wikipedia.
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