A Giant Eye Seen from Orbit

NASA has released new satellite imagery of the Richat Structure, a massive geological formation located in the Saharan desert of Mauritania, West Africa. Nicknamed the "Eye of Africa," this concentric ring formation stretches roughly 50 kilometers in diameter — vast enough to be clearly visible from orbit.

Why It Matters

The Richat Structure has captivated astronomers, geologists, and astronauts for decades. Crews aboard the International Space Station (ISS) have long used it as a navigational landmark while passing over the Sahara, a testament to its unmistakable visual presence from space.

Geologically, the formation was once mistakenly thought to be a meteorite impact crater. The current scientific consensus, however, holds that it formed roughly 100 million years ago when a dome-shaped rock uplift was gradually worn down by erosion, exposing concentric rings of progressively older rock layers toward the center — making it a natural cross-section of Earth's geological history.

A Legacy of Satellite Observation

Since NASA's Gemini program in the 1960s, the Richat Structure has been photographed dozens of times by satellites and spacecraft, including the Landsat series, ISS-mounted cameras, and ESA's Sentinel satellites. The latest NASA imagery captures the formation's geological complexity in fine detail, with potential applications in geoscience research and education.

Science's Window into the Sahara

The remote Adrar region of Mauritania where the structure sits is difficult to access on the ground, making satellite remote sensing the primary tool for studying it. NASA's continued Earth observation missions remain essential for advancing scientific understanding of such hard-to-reach natural wonders.