What makes the case of the Millennium Tower sinking so interesting is the fact that it's a newly built skyscraper, which was only completed in 2008.
Two satellites created these data dots to track building movement over a recent one-year period.
The Sentinel-1 study is not focused on the Millennium Tower but is part of a larger mission by the ESA tracking urban ground movement around the world, and particularly subsidence "hotspots" in Europe, said Pierre Potin, Sentinel-1 mission manager for the ESA.
And now new satellite images from the European Space Agency (ESA) confirms the building's shift and shows that the skyscraper is continuing to sink at a steady rate: About five centimeters or nearly two inches a year.
The Millennium Tower is a luxury skyscraper in San Francisco. Nonetheless, and unsurprisingly, the developers are maintaining the building is perfectly safe for occupation, since stating anything less than that would be tantamount to hanging a "Sue Me" sign around their necks.
- Recently released images from space offer a new perspective and new details on the sinking San Francisco high rise that has been dubbed "the leaning tower of San Francisco".
Leaning San Francisco tower seen sinking from space
The image provided by the European Space Agency ESA on Thursday, Nov. 24, 2016, shows the Millennium Tower in San Francisco on the base of modified Copernicus Sentinel satellite data. Yellow-red areas are sinking, while blue areas are rising. There are 950 of them driven 60-90-feet into the ground. Engineers hired by the building and its developers have drilled deep holes around the building to test soil samples to determine if the building has stopped sinking.
The high-rise, like many buildings in San Francisco, is built on landfill instead of bedrock, and experts question whether it would survive a large quake like the famous temblor that almost destroyed the city in 1908.
Now, he's not so sure of that, saying "To have the space agency looking at it debunks what (developers) have put out there. Now we know it's continuing to sink at an accelerated rate", he said. It's also spotted movement in buildings along the Hayward Fault, an area prone to earthquakes, and the sinking of reclaimed land in San Rafael Bay.
In addition to being able to look at the region as a whole, the Sentinal-1 satellite data allows people to examine more specific areas.
California law mandates owners or developers to notify buyers of any problems or building defects and can be prosecuted under civil law for withholding the information. But the situation quickly turned into a war of words, as Johnston mentioned the railway station, and San Francisco's Transbay Joint Powers Authority brought up the foundation argument.