nebäden

Nebäden are a type of cloud formation characterized by their wispy, feathery appearance. They are composed entirely of ice crystals, even when they are at very high altitudes. Nebäden form when the temperature is well below freezing and there is sufficient moisture in the atmosphere to form ice. They are often seen in clear, cold weather conditions.

The term "nebäden" is derived from the Latin word "nebula," meaning mist or cloud. These clouds are typically found at very high altitudes, usually above 20,000 feet (6,000 meters). At these altitudes, the air is extremely cold, which is essential for the formation of ice crystals. Nebäden can appear as delicate streaks, patches, or filaments across the sky.

Due to their composition of ice crystals, nebäden can refract sunlight, sometimes creating optical phenomena such as halos, sun dogs, or light pillars. These displays are a result of the way light interacts with the hexagonal ice crystals. The presence of nebäden can sometimes indicate changing weather patterns, though they are not typically associated with precipitation. They are generally considered a type of cirrus cloud, belonging to the highest altitude cloud genera.