Casa Grande Photogrammetric Test Range information

Casa Grande Photogrammetric Test Range
Casa Grande Photogrammetric Test Range
	Target dimensions of the Casa Grande Test Range crosses

The Casa Grande Photogrammetric Test Range is a test range established in the mid-1960s to test the dynamic performance of aerial survey cameras.^[1] The range consisted of 272 concrete calibration markers embedded into the Earth's surface in and around Casa Grande, Arizona, United States.^[2] The markers are commonly (and erroneously) believed to have been used to aid camera calibration for the US Central Intelligence Agency's Corona spy satellite program;^[3] in fact, they were used as references for aerial surveys through photogrammetry.^[1]^[4] The markers formed a square 16-by-16-mile (26 by 26 km) grid, and were maintained from 1959 to 1972. Some of the original markers can still be found on satellite maps and ground inspection. See links to maps below.

^ ^a ^b Byars, David D. (31 October 1975). "The Casa Grande Photogrammetric Test Range" (PDF). Retrieved 2 December 2021.
^ Cite error: The named reference Hider was invoked but never defined (see the help page).
^ "Corona Test Targets". borntourist.com. Archived from the original on 24 April 2016. Retrieved 29 March 2020.
^ Page II, Joseph T. (21 December 2020). "Candy CORN: analyzing the CORONA concrete crosses myth". The Space Review. Retrieved 25 December 2020.

[Byars-1] Byars, David D. (31 October 1975). "The Casa Grande Photogrammetric Test Range" (PDF). Retrieved 2 December 2021.

[Hider-2] Cite error: The named reference Hider was invoked but never defined (see the help page).

[BT-3] "Corona Test Targets". borntourist.com. Archived from the original on 24 April 2016. Retrieved 29 March 2020.

[tsr-myth-4] Page II, Joseph T. (21 December 2020). "Candy CORN: analyzing the CORONA concrete crosses myth". The Space Review. Retrieved 25 December 2020.