U2 surveillance aircraft criss-crossed the globe photographing everything from 70,000 feet. The pictures, now on display at the Penn Museum, reveal a wealth of archaeological information...Images taken from on high to observe what may be buried underground have been used by archaeologists for more than a century, and researchers at the Penn Museum have embraced the technology since at least the 1920s.But no one has ever utilized the most famous trove of aerial images from the Cold War, those produced by high-flying U-2 spy planes, first deployed by the CIA to photograph all over the world beginning in 1956, a...