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Why is the sky blue and why do we get a sunset

User Jacob Cohen
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7 votes

Answer:

The sun stays in its position at the center of our solar system. It doesn't rise and set. But it appears to rise and set because of the Earth's rotation on its axis. It makes one complete turn every 24 hours.

When sunlight travels through the atmosphere, blue light scatters more than the other colors, leaving a dominant yellow-orange hue to the transmitted light. The scattered light makes the sky blue; the transmitted light ultimately makes the sunset reddish orange.

Step-by-step explanation:

The sky appears blue due to a phenomenon called Rayleigh scattering. When sunlight reaches the Earth's atmosphere, it encounters molecules like nitrogen and oxygen. These molecules scatter the shorter blue and violet wavelengths of light more than the longer red and orange wavelengths.

As a result, the blue light gets scattered in all directions, making the sky above us look blue. This is why we see a blue sky during the day.

Now, let's talk about sunsets. During a sunset, the Sun is lower in the sky, so its light has to pass through a thicker portion of the Earth's atmosphere before reaching our eyes. As the sunlight travels through this larger distance, more of the shorter blue and violet wavelengths get scattered away. This leaves the longer red and orange wavelengths to reach our eyes, giving the sky a reddish or orange hue during a sunset.

To visualize this, imagine sunlight passing through a glass prism. The prism separates the different wavelengths of light, creating a spectrum of colors. When the Sun is high in the sky, the light passes through a shorter path in the atmosphere, resulting in less scattering and a blue sky. But when the Sun is near the horizon during a sunset, the light passes through a longer path, causing more scattering and leaving behind the longer red and orange wavelengths.

So, in summary, the sky appears blue because of Rayleigh scattering, and during a sunset, we see vibrant colors because the shorter blue wavelengths are scattered away, leaving the longer red and orange wavelengths to reach our eyes.

The sky appears blue because of a phenomenon called scattering. The Earth's atmosphere is made up of tiny gas molecules, such as nitrogen and oxygen. When sunlight reaches the Earth, it contains a full spectrum of colors.

The shorter wavelengths of light, such as blue and violet, are scattered more easily by the gas molecules in the atmosphere. These scattered blue and violet light waves fill the sky, making it appear blue to our eyes.

On the other hand, the longer wavelengths of light, such as red and orange, are scattered less and continue on a more direct path through the atmosphere. This allows them to reach our eyes during sunrise or sunset when the sunlight has to pass through a larger portion of the Earth's atmosphere.

During sunrise or sunset, the sunlight travels through a thicker layer of the atmosphere, where more of the shorter blue and violet light waves have been scattered away. This causes the remaining longer wavelengths, like red and orange, to dominate the sky, creating the beautiful colors we associate with sunsets and sunrises.

The sky appears blue during the day because of a phenomenon called Rayleigh scattering. Rayleigh scattering occurs when light interacts with particles in the atmosphere that are smaller than the wavelength of light. In the Earth's atmosphere, the primary particles responsible for scattering are nitrogen and oxygen molecules.

When sunlight enters the Earth's atmosphere, it contains all the colors of the visible spectrum, from red to violet. However, the shorter wavelengths of light (such as blue and violet) are scattered more easily by the molecules in the air compared to the longer wavelengths (such as red and orange). This is because the smaller particles in the atmosphere interact more strongly with the shorter wavelengths of light.

As a result, when sunlight passes through the atmosphere, the blue and violet light gets scattered in all directions by the gas molecules. This scattered blue light reaches our eyes from all regions of the sky, creating the perception of a blue sky.

Now, let's talk about sunsets. The reason we observe a sunset with hues of orange and red is because of the way light travels through the Earth's atmosphere when the sun is near the horizon. During sunset or sunrise, the sunlight has to pass through a larger portion of the Earth's atmosphere, compared to when the sun is directly overhead.

During this longer path through the atmosphere, the shorter blue and green wavelengths of light continue to scatter, but to a lesser extent. Instead, the longer wavelengths, such as red and orange, are scattered more effectively. This scattering of longer wavelengths is known as Mie scattering, and it is caused by larger particles, such as dust, pollution, and water vapor in the air.

Why is the sky blue and why do we get a sunset-example-1
User Sagar Acharya
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27 votes

Answer:

Small particles of dust and pollution in the air can contribute to (and sometimes even enhance) these colors, but the primary cause of a blue sky and orange/red sunsets or sunrises is scattering by the gas molecules that make up our atmosphere. Large particles of pollution or dust scatter light in a way that changes much less for different colors.

Step-by-step explanation:

User Kitze
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