500 years ago, Leonardo da Vinci proposed an unusual theory explaining why the entire surface of the moon can glow at night, even if the sun only illuminates part of it. It turns out that his idea was absolutely correct. Mark Brown witnessed the "da Vinci glow" when he took a picture of the conjunction of the Moon and Venus over Albernett in Iowa (USA).
The da Vinci glow, also known as the ashlight of the moon, refers to the effect when the entire surface of the lunar disk appears visible despite the fact that the part illuminated by the sun may be only a few percent. You can observe it shortly before and shortly after the new moon. For most of human history, people have admired the faded glow of the moon, as if framed by a bright crescent. Until the 16th century, no one could explain the cause of the phenomenon, but Leonardo da Vinci first suggested that sunlight reflected from the Earth illuminates the surface of the satellite. How could he have come to this in the 1500s, when most people did not even know that the earth revolved around the sun? Copernicus's theory was only published in 1543, 24 years after Leonardo's death. An incredible imagination was one of the hallmarks of Leonardo - in his notes there are many sketches of aircraft, tanks, scuba gear and other devices that were fantastic for that era. We can safely say that this man was centuries ahead of his time.
In 1506-1510 in Milan, Leonardo created the Codex of Leicester - this is a notebook of his scientific records about a variety of natural phenomena. There is a page in the notebook dedicated to the moon. He argued that "ghostly radiance" is associated with sunlight reflected from the earth's oceans. 500 years later, we now know that clouds (not oceans) play a big role in reflecting light, but this is not so significant. It can be said with certainty that Leonardo da Vinci understood the basics and the main principle.
The "Leicester" codex is named after the Earl of Leicester, who acquired the manuscript in 1717. The notebook is currently owned by Bill Gates, who bought it at auction for $ 30.8 million. At the initiative of Bill Gates, the manuscript is exhibited in various museums around the world.