The moon is made up of large dark volcanic rocks, and no offense to the moon, but the moon is not like the Earth. Instead of a hot core, the moon is icy and dead. It doesn’t rotate or turn like the earth and faces in the same direction. The moon is white or shiny because the Sun’s light reflects off its surface, making it visible.
The moon is made up of quite dark material. So it only reflects about 12% of the light that hits it. The amount of light bounced back to Earth also depends on the time and place of the moon’s orbit. When the moon’s orbit directly faces Earth, much light bounces back. Because there’s more of the face of the Moon facing the Earth. It is called the full moon. What is the color of the moon? The moon appears brighter gray or white.
Why Is Moon White?
The Moon appears white in color because it reflects sunlight, composed of all visible wavelengths of light. Here are the key factors that contribute to the Moon’s white appearance:
Sunlight Reflection: The Moon does not produce its own light; it reflects the sunlight that falls upon it. When sunlight reaches the Moon, it interacts with the Moon’s surface materials, causing them to scatter and reflect light in various directions.
Reflective Surface: The surface of the Moon, known as the lunar regolith, is made up of a combination of materials, including rocks, dust, and small glassy beads formed by micrometeorite impacts. These materials have properties that allow them to reflect light efficiently across the visible spectrum, resulting in a white or slightly gray appearance.
Lack of Atmosphere: Unlike Earth, the Moon does not have an atmosphere to scatter or absorb specific wavelengths of light. Earth’s atmosphere scatters shorter wavelengths (blue and green) more than longer wavelengths (red and orange), giving our sky a blue color. Since the Moon lacks this atmospheric scattering, it equally reflects all visible wavelengths of light, resulting in a perceived white color.
Lighting Conditions: The appearance of the Moon’s color can vary slightly depending on the lighting conditions. When the Moon is closer to the horizon during sunrise or sunset, it can appear slightly yellow, orange, or reddish. This color change is due to the atmosphere’s scattering, which can selectively scatter shorter wavelengths and allow longer wavelengths to reach the Moon’s surface.
The crust’s rocks of the moon are composed of plagioclase. Plagioclase is the mineral that makes up most of the crust. It is a common white mineral found in igneous rocks. Also, This rock has large plagioclase crystals in it. However, the moon’s whiteness is because of the abundance of plagioclase in the crust. How is it that the crest of the moon contains so much plagioclase? You must look for a half billion years into the past to find out.
Immediately after the moon formed, its entire surface was covered by an ocean. Instead of water, this ocean was made entirely out of magma. The moon was covered in a magma ocean four and a half billion years ago. All rocky planets were originally covered in magma oceans, including the Earth. As the magma cooled minerals as plagioclase formed, it sank or floated in the magma based on density.
The heavier minerals sank to the bottom while the lighter minerals, like plagioclase, floated. The plagioclase is grouped in this top layer to form the crust. It is how the surface of the lunar magma ocean crystallized into plagioclase-rich rock. The result is the white surface that we see today.
Scientific explanation: The moon can appear yellow, gray, or orange, and at other times, it appears white. So what’s going on? The same process makes the Sun sometimes appear in different sizes or colors on the horizon.
When the moon or the Sun is low on the horizon, it shines through more atmosphere. If it encounters things like dust particles or pollution, that’s when it can start to change colors. So it’s an optical illusion, the same one that happens to the Sun sometimes.
When our brains are trying to figure out what color something is, the first thing is how bright it is. Even when the light in a scene doesn’t change, the colors surrounding an object can trick our brains. If brains could accurately measure light passing through pupils, maybe we wouldn’t be tricked by these color illusions.
The full moon gives enough light to cast shadows on the ground at night. But it only looks so blindingly bright in the night sky because there’s nothing else nearby to compare to except the night sky. Instead of measuring the absolute number and wavelength of the moon’s photons, our eyes and brains compare the relative amounts of light given off by two or more objects within our field of view.
The moon only reflects about 13% of the light that hits its surface. But in the night sky, against the dark blackness of space, it’s the brightest thing we can see, so our brains tell us, “That’s white.”
But if you viewed the moon next to Earth, it would be a dark gray, almost like an asphalt road under the same illumination. You can see this dark gray color in photos taken on the moon during the Apollo missions. Suddenly, the moon doesn’t seem bright compared to a white spacesuit.
Why does the moon shine in different colors?
The light angle changes as the orbit changes and fewer light returns to Earth. It only reflects 8% of the light to Earth during the various quarter stages of the moon. The moon has an elliptical orbit. So occasionally, it gets closer. The moon reflects about 20% of the light, and we call this a supermoon.
The light from the supermoon is so bright that astronomers cannot use their telescopes. The moon is made up of ancient volcanic rock, about 4.5 billion years old, and around the solar system’s age. So this is pretty old rock.
Since the moon has no atmosphere, the surface only changes when another space object hits it. For example, an asteroid has caused the moon to have a lot of craters and mountains. As the moon’s orbit angle changes, the angle of the hills and craters also changes. The light from this that’s reflected becomes dimmer. When there’s a sharper angle from the Sun’s light, it causes the craters and the mountains to cast shadows. The moon is less bright at certain times in its orbiting cycle.
The Earth and the moon have a gravitational pull, and the moon’s gravitational pull causes ocean tides. Thousands of years ago, the moon was much closer to the Earth. It means that people in the distant past must have seen the moon larger and brighter in the night sky. The amount of light reflected was a lot more than it is today.
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