DS Superlaser and Doppler Shift

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Augustus
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DS Superlaser and Doppler Shift

Post by Augustus »

Assume for a moment that you have never seen ANH and have no clue what the Death Star, Star Wars, Turbo Lasers or anything else is.

Somehow you have been transported to a position on or near the surface of the DS as it prepares to fire on Alderaan. From your point of view Alderaan is directly ahead in the center of you vision. As you watch the DS powers up and fires its Super Laser at Alderaan (as in the image below *Note the image is not your POV but its close).

Given that the DS Superlaser (SL from here on) was travelling at some appricable fraction of c when it was fired.

Would you expect the light emitted from the beam to be red-shifted as it travells towards its target?

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KhyronTheBackstabber
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Post by KhyronTheBackstabber »

I'm no expert, but isn't red shift only noticeable at great distances?
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Post by Howedar »

Great speeds, not great distances. The reason that we only notice a lot of red shift on distant celestial objects is that... they're going faster.
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Post by Tribun »

I should add, that we DO see Doppler shift when the Falcon jumps into hyperspace. (ref. Saxtons' site)
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Augustus
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Post by Augustus »

KhyronTheBackstabber wrote:I'm no expert, but isn't red shift only noticeable at great distances?
An object must have a large veloctiy relative to the observer, not distance, in order for the visable light emitted from it to exhibit a doppler shift.
Tribun wrote:I should add, that we DO see Doppler shift when the Falcon jumps into hyperspace. (ref. Saxtons' site)
True but that doesnt really have anything to do with the SL beam.
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nightmare
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Post by nightmare »

Analysis of the image suggests that the beam is redshifted.

The start of the beam has a red quotient of 119. Just before the large pulse it is 165. Just before the second pulse it is 186. Just before it strikes the planet, 191.
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Augustus
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Post by Augustus »

nightmare wrote:Analysis of the image suggests that the beam is redshifted.

The start of the beam has a red quotient of 119. Just before the large pulse it is 165. Just before the second pulse it is 186. Just before it strikes the planet, 191.
So, what you are saying is there is a velocity gradiant along the beam?

I'll say it again - the velocity along the SL beam is progressively increasing?

This hardly seems likely, as there is no mechanism acclerating the beam.
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nightmare
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Post by nightmare »

Augustus wrote:
nightmare wrote:Analysis of the image suggests that the beam is redshifted.

The start of the beam has a red quotient of 119. Just before the large pulse it is 165. Just before the second pulse it is 186. Just before it strikes the planet, 191.
So, what you are saying is there is a velocity gradiant along the beam?

I'll say it again - the velocity along the SL beam is progressively increasing?

This hardly seems likely, as there is no mechanism acclerating the beam.
There is visual evidence that turbolasers can accelerate. But this only deals with what we can see of course, and not any invisible lightspeed part. In any case, the beam is getting more red as it moves outward, though not perfectly uniform. Make of that what you will.
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Post by ClaysGhost »

nightmare wrote:Analysis of the image suggests that the beam is redshifted.

The start of the beam has a red quotient of 119. Just before the large pulse it is 165. Just before the second pulse it is 186. Just before it strikes the planet, 191.
This is highly unlikely to be accounted for by redshifting due to doppler effects. We see one of the tributary beams passing a station in the DS, approaching the camera - it should be blue-shifted. Since the beam is so green, any doppler effects in a beam travelling close to the speed of light should produce very, very noticeable red and/or blueshifting effects, because that intense green implies a strongly peaked spectrum (if the beam was white, any possible doppler effect would be less noticeable because shifting the spectrum red or blue-wards wouldn't produce a red or blue peak).
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nightmare
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Post by nightmare »

Mind you, the visible beams are going very slowly at that point.
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