\" \" The beauty of noctilucent clouds on display over Berlin, Germany on a summer night. As far as historians know, these accounts were the first documented sightings of noctilucent — or \"night shining\" — clouds. The color scheme of noctilucent clouds usually ranges from electric blue to silver, although they can also look reddish-orange. Noctilucent clouds form at these altitudes when drifting particles — including dust left behind by meteors — become coated with ice crystals at low temperatures. To quote a July 3, 2018 paper on the subject from Yale Environment 360, noctilucent clouds are currently \"a long-term indicator for climate change.\"