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Old, digitized astronomical images taken before the human spacefaring ageoffer a unique view of the sky devoid of known artificial satellites. In thispaper, we have carried out the first optical searches ever for non-terrestrialartifacts near the Earth following the method proposed in Villarroel et al.(2022). We use images contained in the First Palomar Sky Survey to search forsimultaneous (during a plate exposure time) transients that in addition tobeing point-like, are aligned. We provide a shortlist of the most promisingcandidates of aligned transients, that must be examined with the help of amicroscope to separate celestial sources from plate defects with coincidentallystar-like brightness profiles. We further explore one possible, but not unique,interpretation in terms of fast reflections off high-albedo objects ingeosynchronous orbits around Earth. If a future study rules out each multipletransient candidate, the estimated surface density becomes an upper limit of$<10^{-9}$ objects km$^{-2}$ non-terrestrial artifacts in geosynchronous orbitsaround Earth. Finally, we conclude that observations and analysis of multiple,simultaneously appearing and vanishing light sources on the sky merit seriousfurther attention, regardless of their origin.

Is there a background population of high-albedo objects in geosynchronous orbits around Earth?