Why is the sky blue ??

Did you know, really the sky is not blue, but rather consists of different colors.Sometimes a gray or black (eg, night sky), sometimes red or gold (the twilight sky and the sunrise time of course), often also white or shiny blue.

Apparently the sky is so colorful. So the question then is how can you?

The sky is black of course because there is no sun that shines at night. While the sky is gray indicates there are a lot of dust particles as a result of dirty gases in the air.

When seen again, it turns out the colors of the sky is very closely related to the position of the earth to the sun and the level of cleanliness and air pollution in one place. Besides the two factors, there is one more major factor that causes the colors of the sun, namely the nature of visible light. Remember experiments white light that is passed to the prism is not it? after it is passed by the prism of light breaks down into 7 colors: red, orange, yellow, green, blue, pink, purple. This is one experiment that can be done to observe the visible light. Well, as with the experiment of this prism, white light emitted by the sun is composed of seven colors. Starting from the purple has the shortest wavelength to the red light with the longest wavelength. For more detail, the position of these colors of the wavelength and energy level can be drawn following the light spectrum.

In physics energy E can didefisinikan as kostanta Planck h multiplied by frequency. If the picture above we can conclude that the lambda wavelength is inversely proportional to the frequency v, then the energy will be greater if the wavelength decreases. Means purple or blue light has a greater energy than red light. Well, so we are familiar with the term The Blue Fire. The blue flame is much more 'sharp' than the red-colored fire. Aha.

Back again to the problems of the sun. To get to the Earth, sun and white light must pass through the atmosphere or the air layer around the Earth. Atmosphere is a series of gases (such as Oxygen, Nitrogen, and Carbon dioxide is needed especially in the process of breathing creatures), water particles, and dust. White light is the sun through the mixtures (~ remember percobaaan flashlight emitted into a glass of murky water ~) with different trajectories. As a result of collisions between light particles (photons) and air mixture constituent particles in the atmosphere that we see the sky in different colors earlier. The light will experience a reduction in energy breaks down due to the process of collision with particles and affect the strength of the light reached the Earth.

According to Lord John William Rayleigh, the sky is blue because blue light and the most powerful green emitted by the sun. The blue color is then captured by our eyes, so we say the sky is blue. Similarly, in the evening. The sky is red because it tends to a red light with a wavelength that is able to travel the Sun-Earth.

How can I measure this wavelength? It's simple. The wavelength can be measured by multiplying the distance by 2. Why, it means that this wavelength, the distance back and forth a certain distance wave.