A revolution in thought

[thedoc]

Originally Posted by peacegirl

I'm just wondering if it's not really a law and it was a terrible word for a description, why can't they change it to a word that's more appropriate?

Have you ever heard of a Brontosaurus?

[peacegirl]

Originally Posted by Dragar

Because history has a weight behind it, and sometimes we get stuck with stupid nomenclature. That's why it's important to actually read and study this stuff, rather than regurgitate the names of things from Wikipedia without actually taking time to understand it.

I'll let other people talk about Roemer, but I'm lost as to why you think it's relevant (or his original experiment). We've verified his results with much better experiments since then, and make use of the principles in modern technology. I'm also well aware that explaining things to you is an exercise in frustration.

Why wouldn't you just give me the information so I can check it myself, instead of attacking me personally? Dragar, that's not fair.

[peacegirl]

Originally Posted by Vivisectus

In what way do you figure that?

I figure that because the traveling light reaching the telescope would be somewhat larger, even if it wasn't detectable by the human eye.

[Vivisectus]

But the whole thing about Romers observation does not have anything to do with the size of the images? It is the timing of their appearance that is pertinent.

[peacegirl]

Originally Posted by Vivisectus

But the whole thing about Romers observation does not have anything to do with the size of the images? It is the timing of their appearance that is pertinent.

That is very true, but shouldn't there be a size difference also? I believe this does not prove that he was right unless, and only unless, technology can show a difference in the image size. Does that not make sense to you, or are you trying to sweep it under the rug so that there can nothing to dispute?

[Vivisectus]

Originally Posted by peacegirl

That is very true, but shouldn't there be a size difference also? I believe this does not prove that he was right unless, and only unless, technology can show a difference in the image size. Does that not make sense to you, or are you trying to sweep it under the rug so that there can nothing to dispute?

I am just struggling to follow your logic here. Why don't you break it down a bit and explain step by step because as it is it doesn't make any sense to me. As far as I can tell a size difference would neither prove nor disprove much.

[peacegirl]

Originally Posted by Vivisectus

I am just struggling to follow your logic here. Why don't you break it down a bit and explain step by step because as it is it doesn't make any sense to me. As far as I can tell a size difference would neither prove nor disprove much.

Of course it would. Light traveling through the radius of Earth would render a certain increase in size to the observer, whether it's 10% or 33%, etc. If sight is efferent, we would not see a difference in size, according to the observer, regardless of the distance calculated by the seasonal change.

[Vivisectus]

Originally Posted by peacegirl

Of course it would. Light traveling through the radius of Earth would render a certain increase in size to the observer, whether it's 10% or 33%, etc. If sight is efferent, we would not see a difference in size, according to the observer, regardless of the distance calculated by the seasonal change.

Light travelling through the radius of the earth renders a difference in size? You mean light hitting the earth? what kind of a scenario are you thinking of here?

[But]

Originally Posted by peacegirl

This is what I don't get. If the angle is 50% larger when it's 33% closer, wouldn't this be noticed by our telescopes today? Something doesn't add up. This is important because I want the evidence that shows a difference in size of Io due to the distance light has to travel to the observer. This difference in size would help confirm delayed vision.

Putting the numbers in (How Far Away is Jupiter? | Distance to Jupiter), the difference between angles at minimum and maximum distances is

2 arctan(1822 km / 588000000 km) - 2 arctan(1822 km / 968000000 km) = 0.000002432 radians or 0.502 arcseconds.

The angular resolution of the Hubble Space Telescope is 0.05 arcseconds (HubbleSite - Hubble Is a Reflecting Telescope), so it should easily be able to see the difference. Ground-based telescopes using adaptive optics can achieve the same kind of resolution.

What's the point? Do you think that Jupiter isn't actually at the distance we think it is, but rather orbiting the Earth or something?

[But]

Originally Posted by peacegirl

Of course it would. Light traveling through the radius of Earth would render a certain increase in size to the observer, whether it's 10% or 33%, etc. If sight is efferent, we would not see a difference in size, according to the observer, regardless of the distance calculated by the seasonal change.

So according to efferent vision, whatever that is today, objects that are farther away do not appear smaller?

[Dragar]

I think peacegirl believes there is a massive conspiracy surrounding observations of Jupiter, and she has uncovered it by making the Astute Observation that Jupiter should be smaller when it's further away.

Edit: Nope, nevermind, she's just crazy!

Originally Posted by peacegirl

If sight is efferent, we would not see a difference in size, according to the observer, regardless of the distance calculated by the seasonal change.

[thedoc]

Originally Posted by peacegirl

That is very true, but shouldn't there be a size difference also? I believe this does not prove that he was right unless, and only unless, technology can show a difference in the image size. Does that not make sense to you, or are you trying to sweep it under the rug so that there can nothing to dispute?

The instruments do detect a difference in both brightness and size, it's just not important enough to note in every account, and it doesn't prove anything as far as efferent vision is concerned. As Vivisectus states the timing is what is important and that does prove that efferent vision is incorrect and afferent vision is correct. There is nothing to sweep under the rug, you are just refusing to see the truth.

[Vivisectus]

Maybe you can draw a simple diagram or something, labeling them scenario 1 and scenario 2, and show what you would expect the difference to be? Because right now I am not sure I understand what you are trying to get at.

[thedoc]

Originally Posted by peacegirl

If sight is efferent, we would not see a difference in size, according to the observer, regardless of the distance calculated by the seasonal change.

That is not what your father says in the holy book.

The fact that you are trying to conflate the seasonal change with the change in distance, indicates that you have no understanding of the issue at all.

[thedoc]

Originally Posted by Vivisectus

Maybe you can draw a simple diagram or something, labeling them scenario 1 and scenario 2, and show what you would expect the difference to be? Because right now I am not sure I understand what you are trying to get at.

Peacegirl doesn't know what she's getting at, she's just throwing things out to confuse the issue and throw people off the discussion, so that she can find something to criticize and claim that efferent vision could be true. There is about as much connection between Peacegirls arguments and the subject under discussion as there is between Lessans arguments and what he claims they prove, None at all.

[peacegirl]

Originally Posted by But

So according to efferent vision, whatever that is today, objects that are farther away do not appear smaller?

No But, I'm only referring to Roemer's conclusions as to why there was a discrepancy in his recordings. According to his results this discrepancy was not due to the movement of Io but to the time difference of 17 minutes since it took longer for the light from Io to arrive.

[Vivisectus]

Yes. That is how he explained the difference in the timing of the appearance of the moons. It did not have anything to do with their apparent size. Why do you think taht is relevant, and what would you expect to see if sight was either feerent or afferent?

[peacegirl]

Originally Posted by But

Putting the numbers in (How Far Away is Jupiter? | Distance to Jupiter), the difference between angles at minimum and maximum distances is

2 arctan(1822 km / 588000000 km) - 2 arctan(1822 km / 968000000 km) = 0.000002432 radians or 0.502 arcseconds.

The angular resolution of the Hubble Space Telescope is 0.05 arcseconds (HubbleSite - Hubble Is a Reflecting Telescope), so it should easily be able to see the difference. Ground-based telescopes using adaptive optics can achieve the same kind of resolution.

What's the point? Do you think that Jupiter isn't actually at the distance we think it is, but rather orbiting the Earth or something?

This conversation only has to do with whether the delay of 17 minutes in seeing the eclipse was caused by the length of time it took for light to arrive.
That's it.

[thedoc]

Originally Posted by peacegirl

No But, I'm only referring to Roemer's conclusions as to why there was a discrepancy in his recordings. According to his results this discrepancy was not due to the movement of Io but to the time difference of 17 minutes since it took longer for the light from Io to arrive.

Roemer concluded that the difference in the time of observations of the eclipses of Io, was due to the time it took light to travel the extra distance when the Earth was farther away from Jupiter and the Moon. Inaccuracies in his knowledge and the precision of his instruments led him to count 22 minutes when the actual time is 16.7 minutes, but the concept was correct in that it took light longer to get from Jupiter to his telescope when the Earth was farther away.

[peacegirl]

Originally Posted by Vivisectus

Maybe you can draw a simple diagram or something, labeling them scenario 1 and scenario 2, and show what you would expect the difference to be? Because right now I am not sure I understand what you are trying to get at.

There's nothing different to draw than the diagram already given of Jupiter's Io in relation to the rotation of Earth. What I'm questioning is why there is no indication that Roemer saw any difference in size (or brightness for that matter) as the light reached his telescope. Maybe the difference of 10% (according to Lone Ranger) would be barely noticeable, but this difference would prove it the light that was responsible for this difference in timing, and recorded by Roemer. I can't believe there isn't one video or photo of this occurrence with today's technology.

[Vivisectus]

Ooooo I think I worked it out!

You were trying to find out if increased distance would make the moon appear smaller, which would then change the timing of it's eclipse.

But you just forgot that the same apparent size difference would apply to Jupiter, so it would make no difference.

[thedoc]

Originally Posted by peacegirl

There's nothing different to draw than the diagram already given of Jupiter's Io in relation to the rotation of Earth. What I'm questioning is why there is no indication that Roemer saw any difference in size (or brightness for that matter) as the light reached his telescope. Maybe the difference of 10% (according to Lone Ranger) would be barely noticeable, but this difference would prove it the light that was responsible for this difference in timing, and recorded by Roemer. I can't believe there isn't one video or photo of this occurrence with today's technology.

As far as Roemer's records are concerned,

Observations[edit]

"Most of Rømer's papers were destroyed in the Copenhagen Fire of 1728, but one manuscript that survived contains a listing of about sixty observations of eclipses of Io from 1668 to 1678.[1] In particular, it details two series of observations on either side of the oppositions of 2 March 1672 and 2 April 1673. Rømer comments in a letter to Christiaan Huygens dated 30 September 1677 that these observations from 1671–73 form the basis for his calculations.[2]

The surviving manuscript was written some time after January 1678, the date of the last recorded astronomical observation (an emergence of Io on 6 January), and so is posterior to Rømer's letter to Huygens. Rømer appears to be collecting data on eclipses of the Galilean moons in the form of an aide-mémoire, possibly as he was preparing to return to Denmark in 1681. The document also records the observations around the opposition of 8 July 1676 that formed the basis for the announcement of Rømer's results."

from this article,

Rømer's determination of the speed of light - Wikipedia, the free encyclopedia

Explain the absence of most of Roemers observations, and quite possibly any mention of a difference in size or brightness of the moon Io.

[But]

Originally Posted by peacegirl

No But, I'm only referring to Roemer's conclusions as to why there was a discrepancy in his recordings. According to his results this discrepancy was not due to the movement of Io but to the time difference of 17 minutes since it took longer for the light from Io to arrive.

Then explain what you mean by this:

If sight is efferent, we would not see a difference in size, according to the observer, regardless of the distance calculated by the seasonal change.

[thedoc]

Peacegirl, are you now going to suggest that there was a conspiracy of scientists to destroy the records of Roemer's observations?

[peacegirl]

Originally Posted by But

Then explain what you mean by this:

There was, in fact, a delay. No one is disputing this, but the interpretation may be incorrect, according to this account. It was assumed that he saw the eclipse 17 minutes later due to the delay of light. If that is true, afferent vision is correct because the light would be bringing the image through space/time. Efferent vision states that as long as the object is within the field of view of the telescope, and there is enough light present, we would be able to see the object (the eclipse) in real time. I know you think this is crazy, but I am not convinced until it can be verified that the image of the eclipse gets incrementally larger in size and brightness as the light approaches, even if it can only be picked up by specialized instruments.