Many might not know it, but there are dozens of large, barcode-like paintings across the United States. Just how long have they been there though and what do they do?

Aerial Calibration Targets in the United States Look Like Giant Barcodes

Fort Huachuca in Arizona. (Image: Google Earth/Center for Land Use Interpretation)

You might remember the strange structures spotted via Google Earth in China’s Gobi desert a couple years ago that were ultimately thought to be satellite calibration structures. According to a recent report by the Center for Land Use Interpretation, these two-dimensional structures in America perform a similar function.

Aerial Calibration Targets in the United States Look Like Giant Barcodes

A target in Maryland. (Photo: Google Earth/ Center for Land Use Interpretation)

They’re aerial photo calibration targets, most of which were put in their current locations in the 1950s and 60s by the Air Force and NASA and some are still in use today.

Here’s more about the targets:

The targets function like an eye chart at the optometrist, where the smallest group of bars that can be resolved marks the limit of the resolution for the optical instrument that is being used. For aerial photography, it provides a platform to test, calibrate, and focus aerial cameras traveling at different speeds and altitudes. The targets can also be used in the same way by satellites.

Aerial Calibration Targets in the United States Look Like Giant Barcodes

Eglin Air Force Base, Florida (Photo: Google Earth/ Center for Land Use Interpretation)

The report stated that most of the targets fall within restricted groundspace: Eglin AFB, Florida; the Nevada Test Site; St. Inigoes, Maryland; and Fort Huachuca, Arizona; Wright Patterson AFB, Ohio; Travis AFB, California; Beaufort Marine Corps Base and Shaw Air Force Base in South Carolina.

The Center for Land Use Interpretation reported the largest concentration of the barcode targets — 15 in a 20 mile range — falls within Edwards Air Force Base.

Aerial Calibration Targets in the United States Look Like Giant Barcodes

Edwards Air Force Base (Photo: Google Earth/ Center for Land Use Interpretation)

“There is some variation in the size and shape of the targets at Edwards, suggesting updates and modifications for specific programs,” the report stated. “A number of the targets there also have aircraft hulks next to them, added to provide additional, realistic subjects for testing cameras. Some of these planes are themselves unusual and rare military jets, officially in the collection of the base museum, despite being left out on the range.”

The ones in the Mojave desert, the report stated, have been used to calibrate A12, SR-71 and U-2 planes. Drones also could use these targets to calibrate their surveillance cameras and sensors.

Most of the targets, CLUI stated are on concrete or asphalt consisting of black and white paint in a 78 foot by 53 foot pattern of parallel and perpendicular bars at different sizes.

The CLUI stated that it picked out images of the barcode-like calibration targets from The Art of Citizen Space Exploration, which is running at the University of California Riverside Sweeney Art Gallery from January 19 to May 18.

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(H/T: Business Insider)

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