A rare and glorious display light up the skies above Indonesia. Image: @sipa5402 via TikTok

Get the Popular Science daily newsletter💡

Breakthroughs, discoveries, and DIY tips sent six days a week.

This colorful cloud over Jonggol, Indonesia , is not a portal to the land of Oz. Or the rainbow road into Asgard from Norse mythology. Or even an AI -generated image. They are iridescent clouds , a rare type of cloud that appear when raindrops interact with sunlight.

According to WABC meteorologist Lee Goldberg , the small water droplets or ice crystals inside of the cloud scatter sunlight, diffracting the light into a spectrum of colors.…