Astrophotographer Max Evans published photos of beautiful noctilucent clouds observed over Florida on July 26. They were formed during the launch of the Falcon 9 rocket.
Noctilucent clouds are luminous clouds that can be observed in the northern part of the sky in summer. They appear 1–2 hours after sunset/before dawn and attract attention with their “ghostly” structure (you can see stars through them) and characteristic silvery color, hence their name. They are often confused with aurora.
Research has shown that noctilucent clouds are the highest clouds on Earth. They form in the mesosphere at an altitude of approximately 76–85 km. Clouds consist of very small water ice crystals (up to 100 nm in diameter) that form from dust microparticles. Presumably, its source is micrometeorites. Silver clouds only appear in summer, when the temperature in the mesosphere drops to its lowest point. For them to form, the temperature should be around −120 °C.
However, noctilucent clouds can have not only natural but also man-made origins. For example, they often formed during shuttle launches, whose exhaust consisted mainly of water vapor. Noctilucent clouds are also sometimes observed after Falcon 9 launches, as clearly demonstrated by Max Evans’ photos.
The photos were taken on July 26. On that day, the Falcon 9 rocket was launched from Cape Canaveral with another batch of Starlink satellites. The rocket successfully completed its mission, placing the satellites into the designated orbit. And its exhaust, illuminated by the sun’s rays, formed beautiful noctilucent clouds in the sky above Florida.
