One of the planet’s biggest cities is sinking so rapidly it’s visible from space

Mexico City is sinking at such an alarming rate that it’s visible from the space. Imagery from a powerful NASA radar system is revealing subsidence rates of more than 0.5 inches a month — making the city one of the planet’s fasting-sinking capitals.

The sprawling metropolis, also one of the world’s biggest cities, stretches out across a high-altitude lake and sits atop an ancient aquifer, which provides around 60% of drinking water for the city’s 22 million residents.

Over the years, this aquifer has been so over-pumped that it’s caused the land above it to subside. Over-extraction has also contributed to a chronic water crisis that has left the Mexico City facing a potential day zero, where taps run dry.

The city’s rapid sinking has been exacerbated by relentless urban development, with new infrastructure adding extra weight on top of the clay-rich soil.

Mexico City’s subsidence was first documented in the 1920s, and in the years since, residents have experienced the impacts, with fractured roads, tilted buildings and damage to the train system.

New imagery from the NISAR satellite, a project between NASA and the Indian Space Research Organization, reveals the extent of the problem in startling detail.

NISAR was designed to map some of the planet’s most complex processes and is able to track subtle motions such as land sinking. It’s one of the most powerful radar systems ever launched into space, according to NASA.

Between October 2025 and January 2026, during Mexico City’s dry season, NISAR mapped the movement of the ground beneath the city. Its findings reveal that parts of the city are sinking at a rate of around 0.8 inches a month — that’s more than 9.5 inches every year.

Areas most affected include the Benito Juarez International Airport, the city’s primary airport.

One city landmark reveals the impacts of sinking. The 114-foot high Angel of Independence monument, built in 1910 to commemorate the 100-year anniversary of Mexico’s independence, has needed 14 steps added to its base as the ground beneath it sinks.

“Mexico City is a well-known hot spot when it comes to subsidence, and images like this are just the beginning for NISAR,” said David Bekaert, a project manager at the Flemish Institute for Technological Research and a member of the NISAR science team. “We’re going to see an influx of new discoveries from all over the world.”

The satellite is also able to track other planetary processes such as glaciers sliding or crops growing, as well as natural disasters such as volcanic eruptions.

For more CNN news and newsletters create an account at CNN.com