What exactly is a moonbow, you ask? Well, it looks like a rainbow but is created by moon rays instead of the sun. The Yosemite moonbow occurs only a few times per year when light refracts in the misty spray found at the base of Yosemite’s waterfalls. The conditions must be just so for the beloved moonbow to show itself—clear skies, enough mist, a dark night, and bright, unobstructed moonlight are all non-negotiables. And not unlike the Yosemite Firefall, it's not a common occurence.
While Yosemite National Park is one of the prime spots for travelers to spot an elusive moonbow, other equally misty locales are known to be home to occasional moonbows. Victoria Falls, Niagara Falls, and Cumberland Falls are all prime viewing locations, as are some of the wetter regions of Hawaii and Costa Rica.
But if you’re hoping to set your eyes on one of these fleeting natural wonders anytime soon, predictions place moonbow sightings at Yosemite Falls from June 1st through June 5th. There are a number of locations within Yosemite National Park to view the moonbows, including Bridalveil Fall, Cook’s Meadow, Glacier Point and Ribbon Fall. Hikes range from easy to strenuous, and all call for a camera or smartphone to capture the magic.