Earth’s Largest Mirror Shattered by Science

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In southwest Bolivia, close to the border with Chile, lies what is usually known as “the world’s largest natural mirror.” When it rains on the huge salt flat known as Salar de Uyuni, vacationers flock from around the globe to pose for pictures, hoping to seize themselves, their automobiles, and the encompassing mountains, clouds, and sky completely mirrored in dreamlike mirror scenes. 

Although it may not truly be an ideal mirror. This, in line with researchers who studied the realm utilizing satellite tv for pc imagery, ground-based measurements, and drone information. They reported their mirror-shattering findings in Communications Earth & Environment lately.

The scientists discovered that whereas the ephemeral, shallow lake that varieties at Salar de Uyuni is exceptionally easy and calm, it doesn’t behave like a mirror would, in line with satellite tv for pc information. Particularly within the inside elements that vacationers can’t attain. For a floor to behave like a mirror, variations in its floor should usually be smaller than a wavelength of seen mild. The analysis group analyzed greater than 390,000 radar measurements—the place satellites shoot radio alerts on the water within the salt flat and measure the smoothness of the sign that bounces off of it—collected over the course of about 8 years. The scientists concluded that the salt flat’s smoothness and reflectiveness fluctuate over time and throughout the extent of the floor. 

To verify their distant sensing measurements, the scientists collected information on the bottom final yr at Salar de Uyuni. They used an optical software to characterize the lake’s floor, pairing that measurement with related optical information from drones flying overhead.

It seems that the lake’s floor is lower than uniform. Across its 3,800 sq. mile floor, some patches wrinkle based mostly on environmental circumstances. Remarkably, although, few waves type on the big lake, regardless that winds do push water round. The researchers recommend that the vanity of the momentary lake—it averages lower than an inch deep—and the presence of salt crystals on the floor assist to maintain the water so calm.

While its good mirrorness failed to face as much as strict scientific scrutiny, Salar de Uyuni continues to be a marvel. After a great rain, its a stunning reflection of Earth’s capability to encourage and shock.

Lead picture: Desizned / Shutterstock

• Bob Grant

  Posted on September 26, 2025

  Bob Grant is the deputy editor at Nautilus.