Approximate location: 34°50’12.89″ N 117°44’34.00″ W
If you are trying to calibrate the lens of, say, a satellite pointing at the earth, or a high-altitude “spy plane”, you need something fairly large to look at, with specific markings that you can resolve and verify.
Hence the existence of a number of calibration targets such as these in the middle of the Mojave desert, part of Edwards Air Force Base.
Those who found this (all before the hint) were:
- Nancy Barbato
- Eloy Cano
- Martin de Bock
- Paul Voestermans
- Phil Ower