06/09/2023
The moon's true color is an off-white brown-gray when it is illuminated by the sun on its dusty surface. However, the appearance of the moon as observed from Earth varies due to the modifying effects of our planet's atmosphere. Italian photographer Marcella Giulia Pace, who has been documenting lunar variations for a decade, selected 48 of her images to create a visual comparison of these changes.
The diverse colors we perceive when viewing or photographing the moon are a result of the Earth's atmospheric layers, which are stratified and irregular. When the moon's light passes through these layers, tiny air molecules scatter the light, with blue light scattering more readily than red or orange due to their structural properties. This phenomenon becomes particularly pronounced when the moon is observed through the densest air, such as when it rises or hovers just above the horizon, leading to a reddish or orange hue. Additionally, various materials in the atmosphere, like water droplets, dust, or wildfire smoke, can further influence the path of light and impact the moon's color, with these colors being specific to the materials present in the atmosphere at the time.
Furthermore, the moon's apparent shape is also distorted as its emitted light travels through the stratified layers of the Earth's atmosphere. Since the atmosphere near the Earth's surface is denser compared to the higher altitudes, the path of light passing through these varying densities causes it to bend. As a result, the source of light, in this case, the moon, can appear as a flattened ellipse rather than a perfect lunar disk when observed from our planet.