Skylab crews debriefed several odd sights
NASA, 1973.
This file is a set of technical debriefings from the Skylab crew in 1973 and 1974. The astronauts describe flashes of light they saw inside their eyes, a bright reddish rotating object that was tracked in a similar orbit, and other lights and satellites seen outside the window. It is worth reading not because every item is a mystery, but because it shows that spaceflight produces many different kinds of strange looking things, and the crew worked hard to tell one kind from another.
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