The Sun appears red during sunset because _____

Options

A. of the refraction of the sunlight by the atmosphere
B. the intensity of light reaching the Earth decreases in the evening
C. most of the blue light is scattered away by the atmospheric particles near the horizon
D. light is scattered to a greater extent in the evening due to a slight decrease in temperature

Answer

To answer the question, "The Sun appears red during sunset because _____", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Light Scattering**:
- When sunlight passes through the Earth's atmosphere, it interacts with air molecules and particles. This interaction causes scattering of light.

**Hint**: Remember that different colors of light have different wavelengths, which affects how they scatter.

2. **Longer Path During Sunset**:
- During sunset, the sunlight has to travel a longer distance through the atmosphere to reach an observer on the ground. This increased distance leads to more scattering of shorter wavelengths of light.

**Hint**: Consider how the angle of the sun changes as it sets and how this affects the distance light travels.

3. **Scattering of Colors**:
- Blue light has a shorter wavelength compared to red light. Shorter wavelengths scatter more than longer wavelengths. Therefore, as the light travels through the atmosphere during sunset, most of the blue light is scattered out of the direct line of sight.

**Hint**: Think about why the sky appears blue during the day and how that changes at sunset.

4. **Resulting Color of the Sun**:
- Since the blue light is scattered away, the light that reaches our eyes directly from the sun consists mostly of longer wavelengths, which are red and orange. This is why the sun appears red during sunset.

**Hint**: Visualize the color spectrum and how different colors are affected by scattering.

5. **Conclusion**:
- The main reason the sun appears red during sunset is due to the scattering of shorter wavelengths (blue light) in the atmosphere, leaving the longer wavelengths (red light) to dominate the view.

**Hint**: Summarize the process: longer path → more scattering → loss of blue light → red light predominates.

### Final Answer:
The Sun appears red during sunset because most of the blue light is scattered by the atmospheric particles near the horizon, allowing the longer wavelengths (red light) to be more visible.