Why does the sky change colors at different times of the day?

Answer 1

A scientist called Olber asked the same question, which came to be known as Olber's Paradox. Olber said "If the universe is infinite and static, every line of sight would lead to a star in the sky. Therefore, the sky should be bright at night." However, we know this is not true. This became one of the supporting pieces of evidence for the Big Bang model of the universe, that says the universe is not static, and in fact had a beginning point and is now expanding.

Modern explanations for why the sky is black include; the finite speed of light, and the finite age of the universe. Firstly, the speed of light travels at a constant velocity, therefore the light from very distant stars may not have reached us yet. And secondly, the Big Bang theory suggests that the universe had a beginning i.e. it is finite in age. This means that stars have not existed for all time, so therefore their light may not have reached us yet.

Answer 2

Because there are things called molecules that when hit at an angle, turns the sky different colors. Answer: A bit of background: The white light from the sun is a mixture of all colours of the spectrum. Each colour of light has a wavelengths. The visible part of the spectrum ranges from red light (wavelength =720 nm), to violet (wavelength =380 nm), with orange, yellow, green, blue and indigo between. The human eye reacts most strongly to strongly to red, green and blue wavelengths. This gives us colour vision. The explanation: Light passing through a clear fluid with suspended particles is scattered. Some wavelengths like blue are scattered more strongly. The first person to notice this and experiment with it was John Tyndall in 1859. So he got his name attached to the effect - the Tyndall Effect. He made three important observations: * From the side, (the way we see most of the sunlight in the sky) the beam can be seen by the blue light it scatters * The light seen directly at the end (looking towards the source) is red. This is the way we see the sunlight at sunset

* The scattered light is polarized. This is why polarized sun glasses make some parts of the sky seem darker.

Some early researchers (Tyndall and Rayleigh) thought that the blue colour of the sky must be due to small particles of dust and droplets of water vapour in the sky. Later scientist discounted this and proposed that oxygen and nitrogen molecules are the cause of the scattering.

In 1911 Einstein did the math to prove that the molecules could cause the scattering. Technically the molecules scatter light because the electromagnetic field of the light waves induces electric dipole moments in the O2 and N2 molecules

So just a brief recap of the colors in the sky:

* Red: Light passing through alot of air removing the other spectral colours * Blue: Light dispersed by the Tyndall effect * No colour (BLack of space): No light interacting with the air (night) * Grey: Cloud cover * Brown/yellow: Pollutants in the atmosphere like nitrogen oxides or smoke

Answer 3

Light creates a color spectrum. The elements in its path depend on what color that element turns. This is why water is blue, grass is green, and blood is red. Without light, nothing would have color. Hi Hanna. Sup! Read this in class. From Luke!

Answer 4

The sky is black at night because we are facing away from the sun and are facing space. It is blue during the day due to rayleigh scattering of incoming solar radiation, scattered by the gases in the atmosphere.

Answer 5

As sunlight comes through the atmosphere some of the light is scattered by the Nitrogen in the atmosphere. Blue light is scattered more readily than longer wavelengths. The more atmosphere that the light has to pass through, the more blue light that is scattered out of the light making it redder. So, as the sun gets closer to the horizon the light from it gets redder. The blue light that is scattered out of the sunlight as it rises and sets is what causes the sky to be blue in color during most of the daylight hours.

Answer 6

If it is a sunny day the sky will appear blue because of the sunlight shining through the high atmosphere that contains many particles (small specks) of pollen etc. that cause the sunlight to scatter. Out of all the spectrum colours of sunlight (Red, Orange, Yellow, Green, Blue, Indigo and Violet) it is blue that is scattered the most, making the sky appear blue.

Although, when the sun isn't shining or when it's night the sky appears black because there is no sunlight to shine through those particles in the sky to cause the scattering effect.

Hope this Helps!

Answer 7

Well, our sky is blue. And that means the rainbow makes it yellow. Therefore, the sky changes colors.

Answer 8

A thunderstorm is mostly made up of an enormous, towering cloud called a cumulonimbus. This incredibly tall cloud, which can be over 12 miles tall, blocks out a lot of sunlight.