Noctilucent clouds seen from St Lawrence Bay, Essex on 16 June at 00.46 BST. Photo: Robin Scagell
The night of June 15–16 produced a display of noctilucent cloud (NLC) as seen from the UK. These silvery-blue clouds are at a much higher altitude in our atmosphere than the usual clouds which put an end to our viewing, and are only seen a few weeks on either side of midsummer’s day towards the northern horizon. They are visible when the Sun is well below the horizon, and conventional clouds appear dark against them.
The exact cause of these clouds is uncertain, but one likely theory is that they are ice crystals condensing on dust from meteor particles suspended in the upper atmosphere.
Time-lapse sequences show them moving slowly and creating beautiful intricate patterns on the northern horizon. Should you see NLC, please send a report to the Aurora Section Director, Sandra Brantingham.
A display on June 15–16 photographed behind conventional cloud from Kendal, Cumbria, by Stuart Atkinson
View from St Lawrence Bay, Essex, on 16 June at 2.25 BST by Robin Scagell