The KH-11 was at the time known to be the most significant advance in outer- space reconnaissance. The key… — Seymour M. Hersh

The KH-11 was at the time known to be the most significant advance in outer- space reconnaissance. The key element of the sixty-four-foot-long satellite was a down- ward-looking mirror in front of the camera that rotated from side to side, like a periscope, enabling the satellite to track a single location as it moved across the atmosphere. p. 5

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