Photograph by  Sangeeta Dey, National Geographic Your Shot
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On February 15, 2016, neuropsychologist and National Geographic Your Shot member Sangeeta Dey snapped this photograph of Yosemite National Park's Horsetail waterfall, illuminated by the sunset.

Photograph by  Sangeeta Dey, National Geographic Your Shot

Yosemite’s Sunlit Waterfall Looks Like Glowing Lava

If conditions are right in mid-February, Yosemite’s Horsetail waterfall can gleam a brilliant orange—as if it were a “firefall.”

For a couple of weeks each February, a waterfall in California’s Yosemite National Park appears to be set ablaze by the setting sun, a fleeting evening spectacle known as the “firefall.”

The effect is finicky, requiring superb conditions: The sunset must catch the 1,000-foot-tall Horsetail Fall just right to illuminate the mist with reds and oranges. Plus, there’s no guarantee of a waterfall, as it pours down El Capitan’s east side only if there’s enough water to fuel it.

If all goes well, the Yosemite Valley's rocky peaks progressively coat El Capitan in shadow from west to east during sunset, leaving a narrow swath of light on the waterfall just before sundown. The marked contrast between the glittering mist and muted rock makes the waterfall look like it's glowing.

Fortunately, pediatric neuropsychologist and National Geographic Your Shot member Sangeeta Dey of San Francisco snapped a striking, now-famous photo of the waterfall on February 15, after waiting a full day for clear skies.

“Finally, as the sun's rays moved towards the fall, I saw the color of the water changing,” she wrote in an email to National Geographic. “As [the waterfall] glowed in yellows, oranges and reds, I realized I had tears flowing down. It was a very emotional moment for me.”

Dey wasn’t looking through her camera’s viewfinder when taking the photos, opting instead to trigger the camera’s shutter remotely while she gazed at the waterfall herself.

“This was one time in my life where I was deliberately using my eyes to see the phenomenon [rather] than look through my lens,” she wrote. “I didn't want to miss a second of experiencing it.”

When it comes to photographing Horsetail Fall, Dey is in good company. Though renowned photographer Ansel Adams captured the gleaming waterfall in 1940, the “firefall” didn’t become widely known until National Geographic photographer Galen Rowell snapped a shot of it in 1973. Ever since, photographers have trekked to Yosemite, angling to get a glimpse of the glittering mist.

DIY Firefall

The spectacular sight mirrors an entirely artificial “firefall” that cascaded down the park’s 3,200-foot-tall Glacier Point cliff for more than 80 years.

The fiery tradition was literally kicked off by James McCauley, an Irish-born hotel proprietor who first pushed campfire coals off of Glacier Point’s edge in 1872. According to his son, McCauley continually experimented with the effect until leaving Glacier Point in 1897, occasionally lobbing fireworks and even dynamite bombs off the edge for added pizzazz.

David Curry, who opened a Yosemite campground in 1899, quickly revived McCauley’s pyrotechnics, making it a wildly popular, near-nightly event. Other than a four-year hiatus in the mid-1910s—sparked by conflict between Curry and the nascent National Park Service—the flaming red fir bark continued to fall until 1968, when National Park Service director George B. Hartzog, Jr. ordered that the man-made attraction end.

Dey has seen old photos of the artificial firefall, and she finds them impressive—but not nearly as impressive as what she caught on film.

“This natural phenomenon is just as amazing, if not more,” she wrote. “All it needs is a mixture of a little water and sunlight.”

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