The Chinese spy balloon that flew over the U.S. in February could have been equipped with an advanced sensor capable of seeing through certain materials, according to a leaked U.S. intelligence document.
A previously-unreported document, allegedly leaked with hundreds of others over the chat service Discord, said the balloon’s solar panel array was “more than enough” to power “any” spying tech – including a sensor that can see through some materials and pick up fine details on the Earth’s surface, the Washington Post reported.
Called synthetic aperture radar, the sensor can penetrate darkness, cloud cover, and thin materials, such as tarps, to reveal what is underneath, according to the Post. Instead of capturing optical images, synthetic aperture radar works by pulsing the Earth’s surface with electromagnetic waves, according to NASA.
It is not clear from the document whether the balloon was equipped with synthetic aperture radar. In an image of the balloon included on the document, multiple components were labeled as “unidentified sensor.”
Data from any synthetic aperture radar would have been similar to what could be gleaned via satellite, Paul Byrne, a remote sensing specialist and associate professor at Washington University in St. Louis, told the Post.
The balloon’s path took it over Alaska and a broad swath of the American heartland before it was shot down Feb. 4 over the ocean off of South Carolina. It flew near all three bases where the U.S. keeps land-based nuclear missiles and was observed lingering near one of them in Montana, as reported by NBC.
Anonymous senior U.S. officials told NBC News that the balloon successfully collected U.S. military data, mostly intercepted signals from weapons systems and communications, and transmitted it in real-time back to China.
U.S. officials have publicly maintained that any intelligence gathered by the spy balloon was likely little more than satellites can already pick up.