We earlier discussed the enigmatic discovery of apparent transient sources in wide-angle photographic plates exposed in the Palomar Observatory Sky Survey between 1949 and 1956 in “Objects in Geosynchronous Orbit in the 1950s?” on 2022-05-14. One plate exposed in 1950 showed nine objects which disappeared in subsequent surveys and could not be found with a modern 10.4 metre telescope and CCD detector. These objects are consistent with sun glints from objects in geosynchronous orbit, but the first such satellite was not launched from Earth until 1963. Other transients are observed to occur along a line, which is what would occur during a long exposure tracking the stars, while an object in geostationary orbit would be following the Earth’s rotation.

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