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Samos Ferret
A photo of a Samos F-1 “ferret” signals intelligence satellite.

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In 1974 F.W. Winterbotham, writing in The Ultra Secret, made a rather startling revelation: during World War II a group of British mathematicians had broken the codes of the German Enigma cipher machine and their ability to read German communications played a major role in the war, particularly in the hunt for German U-boats. This was in many ways a key marker in the Cultural Ascendancy of the Nerd, because after that, the boffins of Bletchley Park were often portrayed as geek superheroes. The Enigma secret, US efforts to break Japanese diplomatic and naval codes—particularly the latter’s value to the victory at Midway—all created a sort of mythology around the obscure and abstract art of codebreaking. Ever since, there has been an active cottage industry in the history of codebreaking, with numerous books and movies produced about it.

The story of Cold Wars signals intelligence is less sexy than finding out what commands Hitler sent to his generals.

But although these stories hold a certain fascination for a segment of readers, there remain vast areas of related intelligence collection that have received far less scrutiny from historians. In particular, relatively less attention has been paid to signals intelligence during the Cold War compared to World War II. Part of the reason is that the Cold War was vast and lasted far longer than World War II, making it harder to research and discuss. But there is also the inherent limitation that breaking communications codes reveals what people said, whereas signals intelligence is often focused on better understanding and countering the actions of machines—jamming radar, reading test performance data on missiles, and the like. The story is therefore less sexy than finding out what commands Hitler sent to his generals.

In the past year the National Reconnaissance Office (NRO) has declassified a significant amount of information on the American intelligence satellite program, releasing official histories and more on photo-reconnaissance satellites like Hexagon and Gambit, the Quill radar satellite, and the Poppy signals intelligence satellite system. Regarding Poppy, there are now significant amounts of information to enable someone to tell a moderately detailed history of early American efforts to use satellites to gather up the electronic whispers of Soviet and other radar systems from orbit.

But telling such a story will still be challenging because there remains a lack of information on other American signals intelligence efforts during the same period, the late 1950s into the 1970s. Poppy was a Navy program, and a successful outgrowth of the earlier, very clever GRAB satellite project. But the US Air Force had actually preceded the Navy into satellite signals intelligence satellite development (although the Navy was first to collect the signals), and also operated signals intelligence satellites at the same time that Poppy was flying. Most of that history remains classified, but not all of it. And the bits that have been released over the years are somewhat scattered and incoherent, like finding a box filled with styrofoam packing peanuts and a few handfuls of puzzle pieces that may not all come from the same puzzle. Worse, despite the release of a huge number of documents, there are relatively few photographs or illustrations of the actual hardware, making it difficult to associate all of the words with the actual objects.

There remains a lack of information on other American signals intelligence efforts during the period of the late 1950s into the 1970s.

The Air Force space signals intelligence effort really started with the Samos program, which began in the mid-1950s but really ramped up operations after the Soviet Union launched Sputnik. Despite the declassification of tens of thousands of document pages, Samos remains poorly understood. The most common misconception is that Samos was a film-readout photo-reconnaissance satellite that beamed its images to Earth and was canceled after the successful Corona film-return reconnaissance system became operational in the early 1960s. In reality, Samos was a large program that eventually incorporated five different photo-reconnaissance systems of both film-readout and film-return types. These were designated E-1 through E-6 (E-1 and E-2 were both film-readout systems, E-3 was never built, E-4 was a film-return mapping system that was built but never launched, and E-5 and E-6 were unsuccessful film-return systems). Samos actually continued after Corona was operational, but repeated failures and the declining confidence that intelligence and Air Force officials had in its capabilities led to its eventual cancellation.

In addition to the photo-reconnaissance mission, Samos also consisted, at least initially, of two signals intelligence systems known as “ferrets” and designated F-1 and F-2. Later F-3 and F-4 systems were started, although F-4 was apparently canceled before flying. (Confusingly, it soon became common to refer to satellites launched into orbit as “Flight 1,” “Flight 2,” or “F-1” and “F-2.”) This is where the story starts to get complex, because there are few available details about either of these payloads. However, F-1 appears to have been primarily a test program to prove that it was possible to receive useful signals in orbit and relay them to the ground. This was an open question at first because it was not clear that the signals could be intercepted and then relayed down to the ground without altering them or losing useful data.

Samos Ferret illustration
An illustration of how a Samos ferret signals intelligence satellite would work with its photo-reconnaissance version.

Some information on the early F-1 program has emerged in the form of some photographs and illustrations of the hardware. The F-1 payload was carried along with the first Samos E-1 photo-reconnaissance payload. However, the way it was carried was rather unorthodox. The F-1 payload was not very big and consisted of an antenna, electronic boxes, and other related equipment. But this payload was mounted on top of, and connected to, the E-1 hardware. Thus, the F-1 hardware blocked the E-1’s camera, which could not be used until after the F-1 was jettisoned.

To date nobody has assembled a coherent narrative of what these early satellites were doing, and how they differed from the Navy’s GRAB and later Poppy projects. As a result, the story of the nerds who built the Samos ferrets remains untold.

Only two E-1/F-1 satellite combinations were launched: Samos 1, launched on October 11, 1960 but failed to reach orbit, and Samos 2, launched on January 31, 1961. According to a diagram depicting Samos operations, the spacecraft would orient itself nose down and eject its nosecone. The F-1 payload would be “calibrated” with a signal sent up by a “mobile unit,” which was actually a school bus equipped with various transmitters and other electronics. The diagram does not indicate if the F-1 would be used for actual intelligence collection, or only in a test configuration. After its mission was over, the F-1 would then be ejected and the visual reconnaissance portion of the mission commenced. At present it is unclear if all phases of the Samos 2 mission operated successfully. The Samos E-1 camera system was discontinued and the Samos 3 launch carried the first E-2 camera system. Unfortunately, it blew up on the pad during a September 1961 launch attempt.

Rather surprisingly, the Air Force was relatively open about the Samos program, and there were numerous press articles about it at the time, one of which originated the false claim that “Samos” stood for “Satellite And Missile Observation System.” But by the time of the second launch a cloak of secrecy was descending over the program.

There are other details of Samos F-2 and later variants scattered throughout various declassified documents, but to date nobody has assembled a coherent narrative of what these early satellites were doing, and how they differed from the Navy’s GRAB and later Poppy projects. As a result, the story of the nerds who built the Samos ferrets remains untold.