What Color is The Moon?
Last updated: 2nd of March 2020
Everybody knows that the Moon is mainly grey. Whenever you look at a picture of the moon or looking at it in the sky, you may be familiar with its very monotonous shades of grey. Indeed, the surface of the moon seems to be empty of all the different colors we are used to see on a daily basis on our home planet.
However, upon closer inspection, there might be a few more different shades up there. And that’s due to the fact that different minerals on the moon’s surface reflect different colors.
Why is the Moon grey?
Well, it’s mainly due to the fact that the moon surface is made of the following basic minerals:
Funnily enough, what all those minerals have in common is that, while in dust form, they are all grey.
The other thing is that like all moons and planets, our Moon does not emits light of its own… Moonshine comes from reflected sunlight.
Now lucky for us, there are different shades of grey at play which makes the moon’s appearance a little less boring.
The moon’s surface bears many scars from the constant bombardment from small meteorites, but also older marks from its violent formation. This is what those dark patches (of many shape and size) are on the surface of the moon!
Why can't we see the true colors of the Moon from Earth?
There are a few factors that can affect how we can interpret the color of the moon:
- Where the observer is located (is it heavily polluted?)
- The position of the Sun and the Moon (low on the horizon or high on the sky?)
- The sensibility of the observer’s eye can also filter what they perceive (remember that infamous blue/gold dress going viral on social media?).
This can lead to people to seeing the moon in different colors:
Once the moon reaches a total eclipse, it will appear red to observers on Earth and not black. This is due to some residual sunlight being scattered towards it from our planet’s atmosphere.
The blue moon happens very rarely (hence the famous saying) due to the fact that it usually requires an enormous amount of dust and smoke in the air. So the moon does not change color literally, it’s simply all of the particles in the air that makes the moon appears blue in the night sky. It usually happens after forest fires or volcano eruptions.
This change of apparent color typically happens when the moon is very low on the horizon. Any light emitted from a celestial object that is too low on the horizon will have to travel through a lot more atmosphere to reach you than if it was right above your head in the sky. This means that the light is going through a lot more particles, gases, pollutions which explains the orange / yellowish glow.
The Orange Moon
The Blue Moon
The Pink Moon
What do the scientist say about the colors of the moon?
In orbit around the moon since 2009, the LROC (Lunar Reconnaissance Orbiter Camera) has been taking high-resolution images from the moon for more than a decade now. Some of the close-up images have been processed to differentiate the different materials on the surface of the moon, revealing some subtle nuance of dark blue and dark red, as seen on the picture below.
Let’s talk about Albedo
The albedo is a unit of measurement regarding the reflectivity of a surface. At 0%, the object is perfectly black and does not reflect anything. At 100%, it reflects all the light received. An object is considered “white” above 80%.
Earth has an average albedo of 35%.
What about the moon? Our celestial companion has an average albedo of only 8%, like… coal. So according to this unit of measurement, the moon is almost black…
There seems to be a little bit more to the moon’s colours than just white and grey, and the state of the atmosphere above you may greatly influence what you can observe. There seems to be a greater variety of colours underneath the surface of the moon, although we will only know for sure once man step foot on it again.
In the meantime, you can always look up most night and admire the moon in all its (colourful) beauty.