New York City Skyline
York University researchers Gordon Shepherd and Youngmin Cho set out to figure out what is causing airglow to increase and become visible at specific locations. (Photo : Spencer Platt/Getty Images)

Stories of a nocturnal sun have stumped scientists for hundreds, even thousands, of years. Dating back to ancient Rome, there have been tales of day-like evenings even without moonlight and there are no plausible explanations. Now, researchers may have cracked the case.

According to a report from the American Geophysical Union, scientists analyzed satellite data and suggested that waves in the upper atmosphere gathering over specific locations can boost the naturally occuring phenomenon of airglow, resulting in bright nights.

Airglow is a dull light that comes from the different chemical activities in the upper edges of the atmosphere. The green tint occurs when the molecular oxygen breaks into individual atoms. Upon their recombination, it produces extra energy that casts a greenish tint to…