Bolivia’s Salt Desert Becomes the World’s Largest Sky Mirror for Science
During Bolivia’s rainy season, Salar de Uyuni floods into a 10,000-square-kilometer mirror that makes sky indistinguishable from ground, a natural feature prized by scientists for its extreme flatness and used to calibrate satellite sensors. centimeter-level geodetic measurements show the surface is almost perfectly level (after removing geoid effects), with a history of centimeter-scale elevation accuracy under controlled surveys. The seasonal flooding, which dissolves high spots and redeposits salt in low spots, helps keep the surface within about a meter of level, while beneath lies lithium-rich brine and growing industrial activity. The paradox is that the mirror’s usefulness for calibration can also complicate some laser measurements when the water coverage is at its peak.
