The Development of a 2.4-meter Class Mirror for Space-based and Ground-based Surveillance

This paper traces an important part of the early history of surveillance of the ground from space and of space from the ground. ITEK and the Perkin-Elmer Corp were important providers of optics, including 2.4-meter class mirrors, which were primarily developed for US earth-viewing, as “spy” satellites, and subsequently for tracking ballistic missiles from the ground. Two important satellite programs were the KH-9, known as HEXAGON, which has now been declassified, and the KH-11, originally known as KENNAN renamed as CRYSTAL in 1982, and which remains classified. Perhaps the best-known of these space-based 2.4-m mirrors was used on the Hubble Space Telescope which has steadily produced spectacular astronomical science and continues to do so today. Those same lightweight 2.4-m mirrors were also ideal for use in classified programs deploying fast slewing, ground based telescopes for tracking and imaging Inter Continental Ballistic Missiles (ICBM). One of those surplus lightweight 2.4-meter mirrors was declassified and found its way to New Mexico Tech where it became the basis of the Magdalena Ridge Observatory. This paper traces the history of the lightweight 2.4 meter class mirror and the intertwined relationships between ITEK and Perkin-Elmer. Both companies went through individual transformations, breakups and acquisitions, only to finally come together in the Hughes Danbury Optical Systems company.