Record-Breaking Rainbow Lasts for 9 Hours

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Rainbows are the beautiful result of rain and sunlight combining to make the colors of the light spectrum visible. But these results are often fleeting, rarely lasting longer than an hour.

That is unless you're at Taipei's Chinese Culture University in the Yangmingshan mountain range of Taiwan where a rainbow lasted for almost nine hours.

Visible from 6:57 a.m. to 3:55 p.m. local time on Nov. 30, 2017, the campus mobilized to record the event. University students and staff captured more than 10,000 images of the rainbow to document that it never dissipated or reshaped.

A new world record holder

In 2018, the Guinness Book of World Records analyzed the images and verified that the rainbow lasted 8 hours and 58 minutes — recognizing it as the world record holder for the longest rainbow. The previous record was held by a rainbow that lasted for six hours over Yorkshire, England, in 1994.

"It was amazing. It felt like a gift from the sky. It's so rare!" Chou Kun-hsuan, a professor in the university's Department of Atmospheric Sciences, told the BBC.

Chou and a fellow professor, Liu Ching-huang, led the efforts to document this beautiful sight. You can see one of their videos below.

"After four hours, we mobilized all our students and began to notify everyone in the school to take pictures and send us pictures," Chou said.

As for what caused the rainbow to stick around so long, the university can thank a monsoon that trapped moisture in the air and formed clouds. Couple that with sunlight and a low wind speed, and you have the conditions for a very long-lasting rainbow. Such conditions are apparently quite common in the region, according to Chou.

"I plan to contact the Taipei City tourism department to promote this. 'You can see a nine-hour rainbow in Taipei in the winter, it's amazing! Come to Taipei!'"