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To: LeGrande
Ahh : ) You are afraid to answer my question, that shows progress.

Not at all afraid - but rather your question is irrelevant filibustering :-) You're trying to introduce more aspects then needed in order to confuse the issue. "Go pound a stake in and wait 6 hours," I can already hear you thinking. But we don't need to pound any stakes in or wait 6 hours. Remember, for the use of this thought-experiment, we've got a sensitive gravity meter which we've agreed tells us exactly the current position of pluto, and a nice sundial that tells us the exact optical position of the sun. We can operate both instruments at the same time right next to eachother. We don't need to wait and we don't need to talk about the light's path from sun to Pluto to us -- all we need to do is measure the angular difference between the gravitational pull and optical angle! Just like we did for the sun, where you claim that the gravity is 2.1 degrees off from the optical position at any given instant, for a viewer on earth, due to the fact that the earth rotates 2.1 degrees in the 8.3 minutes it takes the sun's light to reach the earth.

If light was instantaneous then you would be correct. The problem for you is that light is not instantaneous.

I well know that light is not instantaneous and travels at about 300MM/S. I also well know that by the time a given light wavefront reaches me from Pluto, the earth will have rotated 102 degrees and the apparent position of Pluto (along with the stars) will also have appeared to move by 102 degrees -- but the gravity will still be coming from about the same place as the light - because it's the earth that rotated, not Pluto that moved 102 degrees!

Using the rotating earth as your frame of reference and recognizing that the light that you see originated 6.8 hours earlier from Plutos actual position, yes, from your perspective, Plutos apparent position is off by 102 degrees (close enough for government work anyway : ) ).

Yeah yeah I well know that the earth rotates about 102 degrees in 6.8 hours! I also know that the light I would see from Pluto is 6.8 hours old. But that's not the issue here! You claimed that at a given instant, the gravitational(and actual) direction of the sun is 2.1 degrees ahead of its optical/apparent direction for an observer on the earth.

You still didn't answer my question! I asked you how much was the angular seperation between the actual(gravitational) position and optical position! (I also asked about a heavenly body that was 12-light hours away.)

So are you saying that if I were to see Pluto in my telescope (granted my telescope is not good enough I'm sure) that at the instant I saw it, Pluto would actually be 102 degrees off and not even in the night sky, most likely?

You seem afraid to answer this question. Why is that? You answered it readily for the sun. Now for Pluto!

Thanks,

-Jesse
148 posted on 08/03/2008 5:18:24 PM PDT by mrjesse (Could it be true? Imagine, being forgiven, and having a cause, greater then yourself, to live for!)
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To: mrjesse
I well know that light is not instantaneous and travels at about 300MM/S. I also well know that by the time a given light wavefront reaches me from Pluto, the earth will have rotated 102 degrees and the apparent position of Pluto (along with the stars) will also have appeared to move by 102 degrees

You have it right, my job is done. That wasn't so hard was it.

Yeah yeah I well know that the earth rotates about 102 degrees in 6.8 hours! I also know that the light I would see from Pluto is 6.8 hours old. But that's not the issue here!

It is precisely the issue.

151 posted on 08/04/2008 5:52:35 AM PDT by LeGrande
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