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I am pretty sure that I used the term aberration of light not stellar aberration. I might have used the term in replying to you and Ethan because both of you started using the term.

You were the first to use "Aberration" in this thread, in 506, and it is true that you didn't specify what type of aberration and since it seemed that Stellar Aberration was the most common meaning of "aberration", so I assumed you meant Stellar Aberration.

Then in 508 you gave the snow example.

Then, in 509 I replied "There are several types of aberration of light - but I'm assuming you're talking about stellar aberration of light since you did not mention - let me know if you were talking about another and we'll address that one."

Then again in 528 you gave the "Falling snow" example - which is unquestionably an illustration for Stellar Aberration and only Stellar Aberration!

So there's no way out - you had Stellar Aberration in mind. You used the word Aberration (which is different then "light time correction") and you gave two examples of stellar aberration (i.e. snow or rain falling). Now you may change your mind - but the fact that you gave the falling snow experiment (Twice!) is evidence that you had indeed in your mind Stellar Aberration - which is unrelated to distance to the sun and nowhere near 2.1 degrees.

The other thing is that stellar aberration illustrates that the apparent position is not identical to the actual position and I have been trying to use every example I can think of. Trying to get this very simple concept (apparent vs actual position ) across is like pulling teeth.

Stellar Aberration only accounts for about 20 arc seconds of apparent angular displacement. I have no doubt whatsoever that the sun is apparently 20 arcseconds displaced due to the transverse velocity (sideways) of the earth as it orbits the sun. But 20 arcseconds is 0.000277777 degrees. You're talking about 2.1 degrees, which is seven thousand five hundred times bigger! Don't forget that you're the one who's arguing that the sun's apparent position is lagged by 8.2 minutes and 2.1 degrees behind its actual position!

So which phenomenon is it that you are claiming causes 2.1 degrees and 8.2 minutes lag in the optically measured angle of the sun as compared to its actual position? Stellar Aberration? Light-time correction? Please choose one (or another if that's what you're claiming.) So far you're being very vague and not committing to either/anything, and then switching to whichever one you like when one gets debunked as the cause. I appreciate that you're in sort of a bind here, but it would help if you figured out what it is you're trying to say and say it!

Thanks,

-Jesse

Let me give you a little tutorial in observation and stellar aberration.

The first thing that is factored out in making observations is the rotation of the earth. Observatories are specially built so that their rotation cancels out the earths rotation. You can even buy relatively cheap automated telescopes that do the same thing. The fact that the earth is spinning is of no interest to anyone, it is a bother. It is important to understand the concept but we have bigger fish to fry : )

Now there is another problem, the astronomers would like to know the distance to the objects that they are observing. You measure distance by the difference in the angle that each eye sees an object. If you only had one eye, your depth perception would be terrible.

Astronomers start with two problems, one they typically only have one eye (telescope) and the light from these distant objects is parallel. So even if they had two telescopes it would make no difference. Even if they make an observation in June and another in December the light rays are still parallel and they can’t triangulate the position. They even have this problem observing items in our solar system. Put two observers a thousand miles apart and have them observe the sun at the same instant, their lines to the sun will be parallel.

So now we come to stellar aberration we know that the earth is traveling through space (our solar system is traveling through space) the fact that our solar system is traveling through space distorts the apparent position of the stars in much the same way that that our angular velocity does, except to a much lessor degree. And they would like to eliminate the stellar aberration too. So, some observatory’s automatically compensate for it too.

Essentially the two concepts boil down to the difference between angular velocity and straight velocity, but the effects are identical. That is why I am more than willing to switch back and forth.