Nigeria.Jos · the flashing light a missionary pilot saw (1966)

On Saturday 2 April 1966, at 18:24 GMT —19:24 local time—, Bob Ediger, a pilot with the aviation department of the Sudan Interior Mission in Jos, on the central plateau of Nigeria, was watching the sky for satellites when he saw pass directly overhead, heading east, what he described as "a most unusual device". The next day he told NASA about it in an air letter addressed simply to "National Aeronautics and Space Administration, Cape Kennedy, Florida", apologising for the vagueness of the address.

Two things struck him as strange. The first was its speed: in the 50 to 80 degrees of arc through which he followed it, no more than a minute elapsed. The second was that it blinked very brightly about twice a second, and between flashes seemed invisible. Its brightness was at least that of a first-magnitude star, and directly overhead much greater; its colour, that of a white star. There was no sound, and Ediger stressed that Jos is very quiet and high-flying jets are easily heard. He gave his credentials: more than 4,000 flying hours, including time in US Air Force F-84G jet fighters. "I have seen many satellites," he concluded, "and in my opinion this object was neither a satellite or an aircraft."

The letter, sent by Nigerian airmail, reached the Office of Information of the Secretary of the Air Force on 21 April 1966 and passed to Blue Book, which opened a card: one civilian witness, ground-visual observation, one object, course east, one minute, no photographs or physical evidence. The conclusion was "possible aircraft", with an unusual note: "in view of experience of observer, not a firm identification". The project thus acknowledged that its own explanation clashed with the testimony of a pilot who said he had ruled out precisely that possibility.

It is the corpus's first case in Nigeria, and its witness is among the best an isolated sighting can have: a professional pilot, with military jet experience, used to watching satellites and familiar with the sound of aircraft passing over Jos. Blue Book took him seriously enough to admit its conclusion was not firm. But a single witness, with no photograph or other observation, leaves the case open to ordinary explanations the witness himself could not fully rule out.

The most likely is a satellite or a piece of rocket debris tumbling end over end. At 18:24 GMT the Sun was some 13 degrees below the horizon at Jos: the sky was already dark, but anything more than about 160 kilometres up was still sunlit, the typical conditions for seeing satellites after dusk. A low-orbit satellite passing through the zenith covers about a degree per second, exactly the speed Ediger described, and makes no noise. Rapid flashes are the signature of a spinning object, above all rocket stages, whose surfaces catch the Sun on each turn; some debris flashes several times a second. Blue Book's alternative, a very high aircraft with an anti-collision light, explains the blinking but clashes with the lack of sound in so quiet a place.

We have not checked which satellites passed over Jos at that time, so the identification remains a hypothesis. But the whole —uniform, straight, silent motion, through the zenith and shortly after sunset— fits an object in orbit better than anything else. That is why the case weighs mainly on the mundane explanation, with a remainder of indeterminacy for the lack of a second observation.

The case also illustrates how many foreign reports reached Blue Book in the 1960s: not through military channels, but through private letters to NASA or the Air Force, often with approximate addresses, which someone in Washington forwarded to the project. Ediger was not expecting an investigation; he wanted to know whether there was a satellite that explained what he had seen, and the file contains no reply.