Noctilucent clouds are phenomena seen during the summer twilight (June and July for the northern hemisphere and December and January for the southern). It is caused by sunlight striking stratus clouds at a height of around 82km.

Honor Wheeler’s Images

Noc_HW01

Noc_HW02

Simon Dawes’ Images

NLC_SD01

NLC_SD02

NLC_SD03

NLC_SD04

Martin Crow’s Images

Nocti_1_mvc

nocti_2_mvc