On 20 July, Kita Nippon News was flooded with pictures and reports of high rainbow activity out of Toyama Prefecture. In particular was this shot of a rare rainbow cloud. Well, actually it was one of those artificial clouds left by aircraft called contrails, but it was still pretty cool.

Actually if we’re going to get really nitpicky then a rainbow wasn’t involved either. It was similar phenomenon known as a “halo” caused by light refracting on ice crystals high in the atmosphere.

According to one eyewitness who was spending the day at the beach first there was a “double rainbow” circling the sun (halo). The woman was able to resist crying at it in joy and tried to photograph it. However, as she went to take the picture she found that the outer halo had crossed through a contrail causing it to glow beautifully in seven colors.

This combination of phenomena had resulted in yet another phenomenon called a circumhorizontal arc. Much like the woman described, this is when a halo passes through some high-altitude ice crystals and produces a colorful looking cloud. Another name for this is a “fire rainbow” due to it’s beautiful resemblance to fire.

Depending on the part of the world you’re in these events can range in frequency from fairly common to extremely rare. Judging by the reaction from people in Toyama, it’s pretty rare there.

Source: Yahoo! News (Japanese)