A striking mosaic assembled from imagery captured by an International Space Station astronaut in 2016 reveals a dramatic optical phenomenon over Lake Powell in Utah. The composite highlights a “sunglint,” a rare event where sunlight reflects off a water surface directly into the line of sight of an observer in orbit, creating a brilliant, mirror-like gleam.
Typically, sunglint is visible only over a limited area of a reservoir. However, by stitching together multiple photographs as the angle of reflection shifted along the length of the waterway, the entire snaking body of water appears illuminated, resembling a giant silver serpent winding through the landscape.
Lake Powell is a massive artificial reservoir situated on the Colorado River within Glen Canyon. Stretching from approximately 70 miles southwest of Moab, Utah, to about 60 miles northeast of the Grand Canyon in Arizona, it is the second-largest reservoir in the United States, trailing only nearby Lake Mead. When at full capacity, the reservoir holds roughly 1.2 billion cubic feet of water.
The lake came into existence in the 1960s following the completion of the Glen Canyon Dam in northern Arizona. It took approximately 17 years for the reservoir to fill completely, causing water levels to rise by around 200 feet (60 meters) over two decades. Beyond its role in hydroelectric power generation, the lake has become a significant tourist destination.
The reservoir is named after John Wesley Powell, a former director of the U.S. Geological Survey who explored and mapped Glen Canyon and parts of the Colorado River in the late 1860s. In his 1875 book, “Canyons of the Colorado,” Powell vividly described the area as a labyrinth of overhanging cliffs, hanging gardens, natural arches, and colorful buttes. He wrote of gliding past “towering monuments” and “mounded billows of orange sandstone,” captivated by the wonders of the canyon.
While some of these geological features, such as smaller branching canyons and a prominent doughnut-shaped depression known as The Rincon, remain visible, many of Powell’s described sites are now submerged. The Rincon, a former river loop that dried out thousands of years ago after a canyon collapse rerouted the water, appears in satellite imagery as a dark ring surrounding a bend in one of the lake’s widest sections.
Notable submerged landmarks include the Music Temple, a side canyon renowned for its exceptional acoustic properties. During drought periods when water levels recede, other lost treasures occasionally resurface; in 2023, researchers discovered rare fossils of a mammal-like Jurassic creature beneath the high-water mark.
In recent years, environmental organizations have advocated for draining Lake Powell to restore Glen Canyon to its natural state, arguing that such a move could relieve pressure on the Colorado River, which has experienced significant water loss in recent decades. However, experts indicate that this scenario is unlikely to occur.
Is the silver appearance permanent, or does it only happen with that specific sun angle? I’d love to see it in person someday.
I had no idea Lake Powell was this big. The scale from space must be mind-blowing to see the whole thing at once.
That composite image is absolutely stunning. It really does look like a shimmering serpent carved through the canyon walls.