A ghostly glow illuminating the moon will be on display this week, but there will be no mystery about it, thanks to Renaissance inventor and artist Leonardo Da Vinci.
Da Vinci studied the skies and became intrigued by the faint outline of the moon that happened at certain times when there was a crescent moon on the horizon at sunrise or sunset. The crescent part of the moon glows brightly, but the rest of the moon is visible as an overcast.
It struck Da Vinci as odd, so he set out to discover how the moon could appear this way, according to NASA.
Because of his work, the phenomenon became known as the “Da Vinci glow.”
The glow is not due to the moon illuminating itself, Da Vinci discovered. Instead, it is created by light from the Earth, whose light can illuminate the night sky 50 times more brightly than that of a full moon, according to NASA.
Da Vinci, working on the knowledge available at the time, made a drawing that appeared to show the phenomenon. It was discovered in his notebooks and commemorated his scientific writings.
According to NASA, there is a page in the “Codex Leicester” titled “Of the Moon: No Solid Body is Lighter Than Air.” In the entry, Da Vinci noted several ideas, including a theory that the moon has an atmosphere and oceans.
Da Vinci also wrote that he believed that the moon was a reflector of light and that the glow of “Earthshine” was due to sunlight bouncing off the Earth’s oceans and hitting the moon.
According to NASA, Da Vinci was close – the primary source is light reflected off clouds.
The phenomenon is easier to see when a slim crescent moon is visible close to the horizon during the first or last few days of the moon’s orbit.
The best days to see it in the next few days is after sunset on Sunday, Monday and Tuesday, according to Live Science. Try looking at the sky in the hour following sunset.
You do not need any special equipment to see the Da Vinci glow.