Viral ‘Rainbow’ Cloud Over Indonesia Confirmed as Rare Iridescence

Overview

• Residents filmed the rainbow-like cloud over Bogor and Bekasi on May 1, and the clips went viral.
• Reporters and meteorologist César Soares verified it as a real case of cloud iridescence.
• The colors appear when sunlight diffracts through very small, similar-size droplets or ice crystals inside a cloud.
• NASA notes the effect shows up in thin, newly formed clouds such as altocumulus, cirrocumulus and cirrus, and the colors can fade within minutes.
• Soares cautioned that smartphone filters or processing can pump up the saturation even when the spectacle is natural.