So, what does this have to do with the sky being blue? Nearby is another molecule just like you. It pretty much ignores you and your friend and keeps heading straight down to the ground.
- Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing ''Hoax''.
- مواقع Google: تسجيل الدخول;
- Circleway, The Story of the Womens Dream Quest!
- A Whisper of the Romantic in the Eye of God!
- Youth Staff Picks.
- Lake Michigan Backroads: Your Guide to Wild and Scenic Adventures in Michigan, Wisconsin, Illinois, and Indiana: Your Guide to the Wild and Scenic Adventures ... Illinois, and Indiana (Backroads of ...).
- Flashcard Study System for the CPIM Strategic Management of Resources Exam: CPIM Test Practice Questions & Review for the Certified in Production and Inventory Management Exam.
In the case of this red light, the Sun is like a flashlight, a shining source of red light in one small part of the sky. All the red photons the Sun emits come straight from it to some observer on the ground. It smacks into your friend, rebounds off him, and obligingly happens to head toward you.
From your point of view, that photon comes from the direction of that molecule and not the Sun. Of course, after it hits you that photon can rebound off you and go off in another direction. A third nitrogen molecule would see that photon as coming from you, not the Sun or the first molecule. When a blue photon from the Sun gets scattered around, at some point it will hit some final air molecule near you, go through a final scattering, and head into your eye. Blue photons, however, with their considerably shorter wavelengths, bump and careen around as they are scattered by molecules in the air.
Profile - Roblox
By the time they reach your eye, they appear to be coming from everywhere in the sky, making it look blue. These molecules are all over the sky, while the Sun is in one little part of the sky. Since blue photons can come from any and all of these molecules, the effect is that it looks like blue photons are coming from every direction in the sky and not just the Sun.
Those blue photons are converging down on you from all directions so that it looks to you like the sky itself is giving off that blue light. The yellow, green, orange, and red photons from the Sun get scattered much less than do blue ones, and so they come straight at you from the Sun without having suffered all those scatterings. There are two reasons why the sky is blue and not violet. The other reason is that your eye is more sensitive to blue light than it is to violet.
Maybe you'll also like:
You can actually test this scattering idea for yourself in the safety of your own home. Get a glass of water and put a few drops of milk in it. Mix in the milk, then shine a bright white flashlight through the mixture. Go to the side and you will see the milk is bluer. Some of the blue photons from the flashlight are scattered away from the direction of the beam and go out through the sides of the glass, making the light look bluer. The light that passes all the way through is depleted in blue photons, so it looks redder.
This also explains the very common effect of red sunsets. One of the lesser known aspects of living on a big curved ball like the Earth is that as the Sun sets, the light travels through thicker and thicker air. When the Sun is on the horizon, the sunlight travels through a lot more air than when it is up high during the day.
Although blue light gets scattered a lot more than, say, yellow light, the yellow photons do scatter a little. When the Sun is on the horizon, the number of scatterers increases enough so that even green and yellow light can be pretty well bounced away into the rest of the sky by the time the sunlight reaches your eye.
List of every PC game checked by System Requirements Lab
Since now the direct sunlight is robbed of blue, green, and yellow, only the red photons which have longer wavelengths make it through. Even green and yellow photons scatter away through the longer path they travel from the horizon, making the Sun look red or orange when it sets or rises. It can look like that when it rises, too, but I think more people are awake at sunset than sunrise, so we see it more often in the evening. Under unusually good conditions it can take on a startlingly eerie blood-red appearance. Sometimes, when there are big volcanic eruptions, the sunsets are spectacular for quite some time afterwards.
Have you ever noticed the Sun looking squashed when it sits on the horizon? The atmosphere, like a drop of water, can bend light. The amount that the light gets bent depends on the thickness of the air through which it travels. That bends the light more from the bottom part of the Sun. The air bends the light up, toward the top half, making the Sun look squashed. As it sets the Sun looks normal horizontally, but it becomes more vertically challenged. The squashed, glowing, magenta Sun on a flat horizon is a sight not soon forgotten.
And now we have the three reasons the sky appears blue. First, the Sun sends out light of all colors. Second, the air scatters the blue and violet light from the Sun the most. And third, the Sun emits more blue than violet light, and our eyes are more sensitive to the blue light, anyway. If asked, I would say that the Sun is yellow. I think most people would, too. Yet we just went through a lot to show that sunlight is actually white. If the Sun is white, why do we think it looks yellow? They reflect all the colors that hit them equally, so if they look white the Sun must be white.
Try this simple test: go outside and hold up a piece of white paper. What color is it? Okay, duh, it looks white. It looks white for the same reason clouds do. It reflects sunlight, which is white. This brings us back to the original question: why does the Sun look yellow? I have to cop out here. Some people think the blue sky is to blame. If blue light is being scattered out of the direct sunlight hitting our eyes, the resulting color should look yellowish.
Most of them come straight to your eye, unimpeded by air molecules. Another common idea is that the Sun looks yellow because we are comparing it to the blue sky. Studies have shown that we perceive color not just because of the intrinsic properties of the light but also by comparing that color to some other color we see at the same time. In other words, a yellow light may look even yellower if seen against a background of blue.
There is another possibility. When the Sun is up high, you can never look directly at it. Your eyes automatically flinch and water up, making it hard to see straight. You can only see the Sun from the corner of your eye. As was mentioned before, at sunrise and sunset the Sun can look remarkably red, orange, or yellow, depending on the amount of junk in the air. Also, the light is heavily filtered by the air, making the Sun look dim enough to be bearable to look at. This may also play a part in the perceived color of the Sun.
- Technical and budget limitations;
- SAT Subject Test: Chemistry Crash Course (SAT PSAT ACT (College Admission) Prep).
- 0 to 1-year-old Favorites (P).
- Exodus (Larkspur #1);
- Stolen Child.
Since it looks yellowish at the only time we can really see it, we remember it that way. This is an interesting claim, although I have my doubts. I have heard some people claim the Sun does look white to them, but I wonder if they know that sunlight is supposed to be white, and have fooled themselves into thinking it is white to them. It still looks yellow to me, and I know better. We know it produces less violet than blue; literally, fewer violet photons come from the Sun than blue.
But which color is strongest? The answer is: green. It just produces more green than any other color.
When they are all combined, our eye still perceives the light as white. Or yellow. Take your pick. Okay, I lied a minute ago; I still have one more question. Of course, they do reflect it a little; they look more steely on overcast days and bluer on sunny days.
But the real reason is a bit subtler.