A sunset occurs when the sun dips below the horizon, marking the end of the day. This natural phenomenon is caused by the Earth's rotation, which causes the sun to appear to move across the sky. As the sun sets, its light passes through more of the Earth's atmosphere, scattering shorter blue wavelengths and allowing longer red and orange wavelengths to dominate the sky. The colors of a sunset can vary greatly depending on atmospheric conditions, such as humidity and pollution. Clouds can enhance the beauty of a sunset by reflecting and diffusing sunlight, creating stunning displays of color. Many people enjoy watching sunsets for their calming effect and the sense of closure they bring to the day.