The reflection of the moon on water, or any other smooth surface, is caused by a phenomenon known as specular reflection. Specular reflection occurs when light rays bounce off a smooth surface and maintain their original angle of incidence. This results in a clear and distinct Shadow and Reflection reflection, where the light rays create a virtual image of the object in the water.
When it comes to the moon's reflection on water, here's how it happens:
Moonlight reaches the surface of the water: The moon emits light due to the sunlight it reflects back to Earth. This moonlight travels through the atmosphere and reaches the surface of a body of water, such as a lake, river, or ocean.
Interaction with the water surface: When the moonlight encounters the water surface, it behaves as any other incident light ray on a smooth surface. Part of the light is absorbed by the water, and the rest is reflected.
Specular reflection: Because the water surface is relatively smooth on a macroscopic scale, the reflected light undergoes specular reflection. This means the reflected light rays maintain the same angle of incidence as the incident rays. The light forms an image of the moon on the water surface.
Observing the reflection: When you look at the water, you see the virtual image of the moon created by the specular reflection. It appears as if there is a second moon on the water's surface, usually shimmering and distorted due to ripples or waves.
It's worth noting that if the water surface is disturbed by wind, rain, or other factors, the reflection may become less clear or even completely disrupted. However, on relatively calm and smooth water surfaces, you can often see a beautiful reflection of the moon or other objects in the night sky.