What color is the Moon?
Have you noticed what color the Moon is in the sky lately? The options «white» and «yellow» are not accepted! The Moon’s color changes, not only because of the weather, but also because of national traditions and whims of astronomers! And today, we’ll tell you all about it.
The main thing—don’t be confused
Every year in April, the Internet is flooded with news about the amazing Pink Moon, which you can observe in the sky when the moon is full.
Pictures like this can often be seen in the news about the Pink Moon. Photo: Dylan Sauerwein / Unsplash
But every year, people are surprised to gaze into the sky, and find that the moon, for some reason, is not pink, but the most ordinary color. And the full moon in April is called the Pink Moon because, in North America in April, phlox blooms—a pink flower!
The fact is that the indigenous people of North America gave each full moon a name, according to the natural features of the season. Many peoples have such names, but today, it is the North American ones that have actively been assimilated into mass culture. Pink, however, is the only «real» color in there.
But national traditions are not the only way to confuse everyone about moon color expectations. The champion of confusion trophy can safely be awarded to the Blue Moon. Think about it! The moon may actually be blue, and not called a Blue Moon. «Blue Moon» is the name given to an astronomical event when there are either two full moons in a month (instead of the usual one per month), or four full moons in three months (instead of only three). And in the latter case, the Blue Moon is considered to be not the fourth (the additional one), but instead, the third full moon.
And the cherry on top is the Black Moon, which is the extra new moon (when, from the Earth’s side, the Moon is not illuminated by the Sun, and is not visible to the eye) of a month or a season. By the way, there is also a Dark Moon—so you can call any new moon this. At least there is some logic here!
Other names of the Moon
Let’s go back to the North American native tribes. They had special names for each full moon (about once a month). And now these names are becoming more and more common in popular culture. Here’s what they call full moons in North America in different months:
- January—the Wolf Moon. Because on cold nights, wolves like to howl at the full moon.
- February—the Snow Moon. February has the heaviest snowfall in North America.
- March is the Worm Moon. In March, the soil begins to thaw, and there is an opportunity to dig for worms. (or for them to prepare the soil for planting!)
- April is the Pink Moon. The pink phlox flower blooms in April.
- May—the Flower Moon. All the other flowers bloom in May!
- June—the Strawberry Moon. The first strawberries are starting to ripen!
- July is the Deer Moon. Young deer grow their antlers.
- August—the Sturgeon Moon. August is considered the best month for sturgeon fishing in the Great Lakes.
- September is the Harvest Moon. This is the traditional harvest month in the Northern Hemisphere, and thanks to the light of the full moon, you can keep working even at night.
- October is the Hunter’s Moon. Wild animals are clearly visible in the harvested fields in the light of the full Moon, coming to eat the leftovers.
- November—the Beaver Moon. Beavers rarely leave their huts in winter, so November is the last chance for hunters to stock up on warm fur before winter.
- December is the Cold Moon. This needs no explanation—
In general, the Moon has always been a convenient reference point on the calendar, and people were attached to the phases of the Moon, in various places for many occasions. For example, in Christian traditions, there is the Lenten Moon (the last full moon of winter) and the Easter Moon (the first full moon of spring). There are so many such examples, that it is nearly impossible to list them all.
«That’s all well and good, but the moon does come in different colors!»
You might say this, and you’d be right. The color of the Moon visible to the naked eye can be quite varied, and is most often related to the weather. Here is a famous collage by Italian astrophotographer Marcella Giulia Pace, in which she has collected photos of the Moon from different regions of Italy.
Photo: Marcella Giulia Pace
It turns out that the Moon can be not only grayish-yellow, but also blue, red, and even purple!
The most frequent of the «unusual» colors are red and orange. The red color is caused by light that is less often scattered on air molecules, and more frequently reflected by dust particles than other colors. Therefore, the Moon turns red either near the horizon, or in dusty air (or, preferably, both at once). The most dust in the air is during anticyclones, so a red Moon is a sign of persistent clear weather.
Photo: Jochem Raat / Unsplash
If, under the same conditions, the Moon rises during the day instead of at night, its red-orange color «mixes» with the blue light of the atmosphere itself to produce a purple Moon.
But more often than not, the Moon looks bluish-white during the day: it’s because the light of the Sun is white, and the sky is blue.
In rare cases, the Moon can also appear to be deep blue. This is due to impurities (mostly smoke) in the atmosphere that absorb the red color. And when a total Lunar eclipse occurs, the Moon is often called a «Blood Moon» because it turns a scarlet color. It’s the same red, only duller and darker.
In fact, all variations of grayish-yellow are caused by the Moon’s different heights above the horizon, impurities in the air, and clouds in the atmosphere.
50 shades of gray
It is now clear that all the colors of the Moon have either been invented by people, or perceived from the vantage point of the Earth. But what color is the Moon in reality? Let’s look at a map of the Moon, based on color photos from space, where there are no color distortions.
Photo: NASA
This palette of colors is not easy to describe, but we will start with: gray. Of course, it’s not all that simple!
Even here, we can see that the Moon’s surface is very heterogeneous, and made up of different rocks. And, although all of them are rather gray, they also have colored shades, poorly distinguishable by the eye. Thus, if you take very high quality images of the Moon and a little «twist» on their colors, the picture will become more diverse.
Image of the Moon with increased color saturation. Photo: Darya Kawa Mirza
Such images are interesting, first of all, for studying the Moon, because they allow us to highlight its different zones, which are almost inaccessible to the naked eye.
The Moon has been with us throughout human history. Hundreds and thousands of years ago, our ancestors gazed into the sky, just as we do today. No wonder the moon has always attracted attention and played a huge role in popular culture. And we, if we wish, can keep these glorious traditions alive!
Text: Eugenio Monti, a meteorologist and a climatologist
Cover photo: Gitte Winter / Unsplash
Read more:
What are the phases of the moon and how to understand them
