Earthshine, Earthlight or planet-shine will be visible this week in the early evening in the ... west just after sunset. VWPics / Universal Images Group via Images
Have you ever seen the ashy glow of the crescent of Moon? Also known as Earthshine, Earthlight, Planet-shine and - perhaps most poetically - as "the New Moon in the arms of the Old Moon", it is a breathtaking sight and it is on view this week at come if you know when and where to watch.
All you need is a clear sky, a good view to the west, and a few minutes to spare in the twilight to subtly see the dark side of the Moon lit up.
This ashy glow is visible for a few evenings after the New Moon at dusk when our satellite appears as a thin crescent in the early days of the Moon's orbit on Earth.
It will be more easily visible in the west during the twilight of MercerSun April 14 to Friday April 16 2021 wherever you are in the world.
It's also visible the few mornings before the New Moon, so as I write this it's Friday April 9 and Saturday April 10, 2021, but since it means getting up one hour before dawn, less people will see it. Or even try!
On a crescent moon, it is sometimes called "the New Moon in the arms of the Old Moon" and on a waning crescent "the Old Moo n in the arms of the New Moon."
What is this earth ray? It is reflected light. That's all. It is the sunlight that hits the Earth and reflects off the Moon, so even if there is only a crescent Moon - that is. the Moon is very close to the Sun and only its side is illuminated - we can see lines on the dark member of the Moon.
You can see this ashy glow with the naked eye, even if a pair of binoculars or a small telescope reveals it beautifully and unmistakably.
The This phenomenon is at its best on either side of a northern hemisphere spring new moon - April, May, and June - when arctic ice and snow reflect the light the most. thick clouds have an impact.
So, is this the "dark side of the moon? " No, such a thing doesn't exist. The moon is locked to Earth , so that it only rotates once every 29.5 days - a full orbit of the Earth. Therefore, 50% of the Moon is always dark and 50% is still illuminated by the Sun, but As the Moon revolves around the Earth every 29 days, we see its illuminated part waxing full and waning to its New phase as it is lost. the glare of the Sun.
Exit so this week and see if youcan find the darker member of a thin crescent moon reflecting sunlight from Earth.
Once you find it, think about this: If you were on the lunar surface only at this time of the month, would you see an almost "full" Earth, which for the most part? of the month grows and decreases practically the same spot of the night sky, never rising or setting.
I wish you a clear sky and big eyes.