if the speed of light is constant explane the blue and red shifts?

Question

that they observe to determine the direction a star is moving in if lght was constant would it not allways be white?

These are very good answers and lend proof to light and sound both being wave principle however we do know that a wave can be passed if enough speed is attainedand causes an effect based on the medium an object is traveling in on this basis i would say that faster than light travel is possable and may display a coronal type effect as the light barriar is broken without the object actually becoming light there by alowing the object to be at a point before it can be seen. can you corroberate for or against this with your knowlage of wave priciple. and thak you.

Answer 1

Actually, if the speed of white light wasn't constant, the blue and red shifts would not occur.
Well... sort of.
The speed of light is always constant relative to one observer (Relativity). No matter how fast you are moving, light is always moving away from you, or towards you, at the speed of light. Therefore, the speed of light, relative to the observer, is always constant. But, the spectrum of observable light changes.
The blue and red shifts occur because of the doppler effect. Blue light has a longer wavelength than red light. That is why when a star is moving away from you it appears to have leaned toward blue, or if it is coming closer, the wavelengths are observed to be shorter, and appear to be red.

To answer what you later added:
No,
You cannot travel faster than light because the amount of energy you would need to reach that speed would be infinite. Therefore your "spaceship" that contains all of this fuel (even if it is nuclear) would have too much mass to get moving.
Also, you talk about needing a medium for a wave to pass through...
Let me start off by saying that there are eleven dimensions. There are "mediums" as you call it even in outer space.

Last, You should go back and read your own writing. Add some puctuation because I have no idea where your sentences end and new ones begin.

Answer 2

This is a very astute question that deserves the CORRECT answer.

Blue shift and red shift is often likened to doppler shifting, but the speed of light is constant no matter what your vantage point is. So why does it occur? The expansion and contraction of spacetime, as predicted by Einstein's General Theory of Relativity is the culprit. As an object moves toward you rapidly, the space between you contracts and the light becomes blue shifted. As an object moves away rapidy, the spacetime between you expands and the light becomes redshifted. The faster an object moves toward you or away from you causes greater shifting, because the expansion or contraction is greater.

Hope this helps

Answer 3

the doppler effect is the reason - tycho put it the quickest and cleanest and most simple. Just to add the light seen from the front or compressed side, would be blue and the trailing seen would be red. Speed of light is constant and the frequency is changed (in a vacuum).

Given: a plane with a white light on top.

In the air, light appears white from all sides as the air and our eyes are used to seeing white light and the retention factor of the eye excludes the color shift.

In a vacuum, the light would appear white only from the side as the plane went by you. Coming at you, blue would be seen. White as it passed, and red as it leaves you. This is the blue and red shift that tells science what direction the universe is moving. Not to be confused with the visible spectrum of color.

Answer 4

No. The color shift is known as the "doppler effect" and is the same effect that causes a train whistle or car horn to appear higher pitch when it is moving towards you and then drop to a lower pitch as it passes you and begins to move away. The speed of the sound does not change but the frequency we hear does. The speed of the object is added to the speed of the sound (or light), and since light is composed of a wide range of wavelengths, we see a shift in color depending on whether the object is moving towads us or away. The light from an object moving towards us will shift towards the shorter wavelengths (ultraviolet) and will shift towards the longer wavelengths (infrared) if it is moving away. Visible light is that part of the spectrum between infrared and ultraviolet; the colors we see are based on frequency, and a light moving towards us at a high rate of speed will appear to become more bluish, while a light moving away from us at a high rate of speed will appear more reddish.

Answer 5

The speed of light is constant. The red and blue shifts are caused by movement of the object being observed. If it is moving towards us, light rays are compressed. If it is moving away from us, light rays are elongated or stretched out. But the light coming from the object is still moving at the speed of light.

Answer 6

Speed of Light IS Constant. What the red and blue shifts measure is not a difference in the speed of light, but a difference in the speed of the object emitting the light. Red and blue shifts are a shift in the frequency of light, not a change in its speed.

The speed is the same. just the frequency is longer (red) or shorter (blue)

Answer 7

The speed of the light remains the same but the light's frequency shifts relative to the motion of the observer and the star.