Every day for decades, engineer Phil Pressel would come home from work and be unable to tell his wife what he'd been doing all day.

Now, Pressel is free to speak about his life's work: designing cameras for a top-secret U.S. government spy satellite. Officially known as the KH-9 Hexagon, engineers called it "Big Bird" for its massive size.

Until the government declassified it last month, Hexagon had been a secret for 46 years.←

https:// www.npr.org/2011/10/29/141824562/spy-satellite-engineers-top-secret-is-revealed?t=1535677793041