Original photo by Gergitek Gergi tavan/ Shutterstock
The sun is the most reliable way to create the gorgeous light display we call a rainbow, but it’s not the only way. After all, the moon illuminates the Earth, too — and rainbows are essentially an optical illusion caused when water droplets split light into its ROY G. BIV components. But seeing a “moonbow” isn’t exactly easy.
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It's a factThe moon experiences four types of moonquakes: deep moonquakes (likely caused by tides), meteorite impacts, thermal expansion when the moon’s frigid crust is warmed by the sun, and shallow moonquakes. This last type of moonquake can even top 5.5 on the Richter scale.
How rare is this nighttime meteorological phenomenon? Well, Aristotle wrote around 350 BCE in his treatise Meteorologica that “it was formerly thought that [rainbows] never appeared by night as a moon rainbow. This opinion was due to the rarity of the occurrence… we have only met with two instances of a moon rainbow in more than fifty years.” So, pretty rare. That’s because for a moonbow to form, you need a variety of conditions to be Goldilocks-level perfect. First, the moon must be low in the sky, and can’t exceed 42 degrees from the horizon. The moon must be full or near full, and you can’t be hanging around any artificial light — sorry, no moonbows in cities. Finally, just like rainbows, moonbows need water droplets in the atmosphere, so waterfalls are often a good spot to go hunting for moonbows. Just don’t expect to see the dazzling array of color typical of a daytime rainbow. Because the moon isn’t as bright as the sun, less light is refracted, and a moonbow usually looks white (at least to human eyes). But if you have a camera handy, long exposure photos will reveal a moonbow in all its colorful glory.
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______ is widely regarded as the “rainbow capital of the world.”
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Hawaii is widely regarded as the “rainbow capital of the world.”
The song “Over the Rainbow” was almost cut from “The Wizard of Oz.”
Featured in the sepia-toned opening minutes of 1939’s The Wizard of Oz, the song “Over the Rainbow” is officially the greatest song of the 20th century — at least according to a 2001 survey by the Recording Industry Association of America. But for a song so beloved in the 85 years since its debut, it’s shocking to discover that Judy Garland’s legendary ballad was almost cut from the film. While considered by many to be one of the greatest films ever made, The Wizard of Oz experienced a famously “cursed” production, involving several directorial changes, dangerous stunt work, and more. After filming finally wrapped in 1939, MGM producers realized that the “curse” wasn’t lifted — the movie was a full half-hour too long. So top brass started cutting scenes with impunity, including whole dance numbers and even entire reprisals of “Over the Rainbow.” Still not satisfied with the running time, the executives even cut Dorothy’s original ballad in a June 16, 1939, preview of the film. Incensed by the decision, associate producer Arthur Freed told studio head Louis B. Mayer, “The song stays — or I go.” Mayer relented, and “Over the Rainbow” went on to delight audiences for nearly a century.
Darren Orf lives in Portland, has a cat, and writes about all things science and climate. You can find his previous work at Popular Mechanics, Inverse, Gizmodo, and Paste, among others.
