Doubts have been raised about the authenticity of a video showing 'figures' on cloud cover(X/@t_paranorm_chic) The video was purportedly filmed by a plane passenger on a commercial airline.

The University of Cambridge study found one in 30 flight miles generated a "persistent" cloud when flying through particularly cold and humid airspace and suggests planes avoid these by rerouting ...

When planes fly through these cloud layers, they can create additional cooling around their wings. This cooling can trigger the supercooled droplets to freeze, transforming them into ice crystals.