Harvard astronomer Donald Menzel later argued that the pilots may have seen ground or searchlight illumination distorted or reflected by haze associated with a temperature inversion, with aircraft motion and optical geometry creating the impression of rapidly moving discs. He also considered reflection-type effects more broadly.
The mechanism deserves to be tested because atmospheric refraction can produce convincing visual distortions. The difficulty here is source-specific: the Air Force weather record for the night was described as sharply clear, with high cirrus and no recorded inversion. Nash later emphasized exactly that point in correspondence with Menzel.
The geometry is also awkward for a simple low inversion/searchlight model because the pilots described the objects first below the aircraft and finally climbing above their altitude. Nash later stressed that the objects moved across the view through three separate cockpit windows, which is difficult to reconcile with a fixed reflection in one pane. James McDonald also used the reported below-to-above geometry in criticizing Menzel's explanation.
That does not prove the pilots' interpretation. It means the named skeptical mechanism is not strongly supported by the weather and geometry preserved in the case file.
COUNTER-HYPOTHESIS · MENZEL / BOYD · TESTED AGAINST CASE-SPECIFIC WEATHER