I'd like to see a link to that text, to see it in context. I'm having a h*ck of a time parsing " that the diameter of the planet in its perigee should appear more than four times greater, than the body of the planet more than sixteen times greater, than it its apogee?" That's a lot of "than"s

Yes, interesting ain't it. Imagine what Copernicus felt when he did the calculations.

It is found in the foreward attributed to Orsiander. The entire book, I think, can be found here. It is near the top and before the introduction. It is entitled..."
FOREWORD BY ANDREAS OSIANDER
To the Reader
Concerning the Hypotheses of this Work"

In it you will find the pharse I quoted.

Your answer is correct, btw, based on memory because my family is "walking out the door" without me if I don't bail.

[Edit after movie, Flyboys, with family: Ok, your answer will be probably be correct once you answer the question. I was dashing and missed the quote marks in your statement.]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Ah, that clears it up. Your original was mangled beyond understanding. That link has it:I don't think this was a critique of Ptolemy, I think it was a fudge for Copernicus. What Osiander was saying, was that Copernicus's cycles could not possibly be true. That they were just a mathematical artifice. Copernicus supposedly was upset by the insertion of this "apology."

Before telescopes, the planets were perceived as having disks, which were just an illusion of their brightness. Venus's disk was thought to be essentially unvarying (because its magnitude is), so Osiander shows that Copernicus's theory could not possibly be true (any more than Ptolemy's). He says the disk would have to be more than four times as wide (true, although it's closer to six times I think). We know today that Venus's (mostly) unvarying brightness is a result of a coincidence: the effect due to proximity is balanced by the effect due to its phases.

What happened with the quote? It looked clean to me.

I disagree, but after reading it several times, I can see where it is a little ambiguous. Nevertheless, the phrase from Osiander, "For these hypotheses need not be true nor even probable. On the contrary, if they provide a calculus consistent with the observations, that alone is enough.", would alone be enough to really torque Copernicus. He spent years, if not decades, researching his theory knowing it would be tried, but Copernicus believed it was the better model because it better represented the true order of the planetary motions.

I think not. Osiander should, and does, respect the observation skills of Copernicus. Supposedly, Osiander is an amateur astronomer himself. He wouldn't praise Copernicus who would clearly know Venus varies little, then claim that is what Copernicus theory does [show huge size variations]. I would bet a banana split that the Copernican model can not produce the __(quiz question amount)_of size increase between apogee and perigee of Venus. However, the Ptolemy model does. Therefore, he must be attacking Ptolemy, not Copernicus.

Yes, and Copernicus knew Venus did not vary much, so his model reflects that limited reflection, so to speak.

Other reasons why I think A. Osiander is attacking Ptolemy...
A.O. defends Copernicus in the opening statement...
"...they will find that the author of this work has done nothing blameworthy."

He shows the duty of an astronomer (ie Copernicus) and implys Copernicus is apt to correctly due the geometry:
"For it is the duty of an astronomer to compose the history of the celestial motions through careful and expert study...he will adopt whatever suppositions enable the motions to be computed correctly from the principles of geometry for the future as well as for the past."

O.A. then goes after those who are not apt with geometry...
"Perhaps there is someone who is so ignorant of geometry and optics that he regards the epicyclc of Venus as probable, or thinks that it is the reason why Venus sometimes precedes and sometimes follows the sun by forty degrees and even more. Is there anyone who is not aware that from this assumption it necessarily follows that the diameter of the planet at perigee should appear more than four times, and the body of the planet more than sixteen times, as great as at apogee?"
He has shown that a problem exists with Ptolemy, IMO, which should encourage the reader to read the book, which is the job of a foreward or introduction.

O.A. further states:
"Yet this variation is refuted by the experience of every age. In this science there are some other no less important absurdities, which need not be set forth at the moment." He did not say "In this book there are... absurdities". He is stating that the traditional science from Ptolemy's work is flawed.

[I knew we should have started a Copernican thread. ]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

I couldn't read it. It was a mess. Wait, it's in the thread. I dunno, I'm pretty sure that that is the interpretation of most historians.The Copernican model is essentially the solar system we have today. I just checked my star map software and it shows a diameter of 57.88" for Venus at next close approach to earth, and 9.72" at its farthest (a few days from now). That's about the six times I mentioned earlier. Ptolemy and Copernicus give about the same results--but of course they would.

Hmmmm. Good point. Why didn't you bet me? [sure glad Ken wasn't around. ]

Both models do produce the same size variation result. I had in my mind that since Venus would go behind the sun in the Copernican model, that it would have the more reasonable solution to the limited variation. It may also have the advantage because the Copernican model can explain the phases observered later by Galileo. But, I must agree with your size conclusion, none the less.

This is not as straighforward as I had thought.

Well, at least you get the cigar as 6x is the answer, and we can move on now.

Very interesting. I wonder which model they really thought supported the observed limited magnitude changes. The Copernican model would demonstrate much greater phase angles so at first glance it would seem to be the problem model. Yet, the greater phase angle comes at greater distances and this would limit magnitude variations, as you have already stated. But did they understand this?

In the Ptolemaic model, the phase angle remains about the same, so maybe they (Osainder) thought this model favored the limiting magnitude variations. Of course, for a somewhat fixed phase angle and a size variation of about 16x, then it would be obvious a much larger magnitude variation would be expected.

Assuming they were this smart, and I'd bet they were (friendly bet only, no precious ice cream), then the Copernican model would clearly make the most sense, and Osiander would then be ridiculing the Ptolemy model, as I felt he was from the context of his preface [foreward].

Whew, I think I'll go back to questions that ask for names of people or things.

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

According to the historians, Osiander was criticizing Copernicus's model, probably as a way to avoid the censors (hey look guys, no one takes this stuff seriously, it's just a computational device).

Here's the setup for my question: everyone knows that Galileo ticked off the Pope, and the Pope prosecuted Galileo and had him under house arrest for the rest of his life. Not everyone knows the name (and number) of that pope, Pope Urban VIII. Galileo's longtime friend and protector was Maffeo Barberini, a former Cardinal, to whom Galileo dedicated his book The Assayer, where Galileo explains the new scientific method. It was published while Urban was Pope, and Barberini received the dedication enthusiastically, according to accounts. Barberini had even written an ode of praise in honor of Galileo.

My question: Because of his sympathies with Galileo, what sort of treatment did Barberini receive from Pope Urban VIII?

Weeellll.

Maffeo Cardinal Barberini was Pope Urban VIII, from 1623 - 1644. As you say, he was a friend of Galileo's before becoming Pope; his opinion was that Galileo's system could well be published as long as he treated his results as hypotheses. He was not in favour of Galileo's sentencing, but went along with it when it happened (you might wonder why he kept a low profile even though he was Pope, and therefore, in command; but Bellarmin was one formidable inquisitore, and one didn't tell him how to run his office, even if you were Pope).

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Non sunt multiplicanda entia praeter necessitatem.

I tried to make it a trick question. You're up, Arneb!

Thanks, hhEb09'1.

The cities of the now defunct GDR (or of other Warsaw Pact countries) may have had nothing much in common with the sprawling, touristy, upscale centres of tourism on Hawai'i's Big Island.

After dark, however, I saw one striking similarity when I visited Hawai'i this past February. While the phenomenon was born out of need in the GDR, it is there by intention in Kona.

What do you think the phenomenon is, and why is it there to see?

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Non sunt multiplicanda entia praeter necessitatem.

Hey, no one here to bludgeon me?

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Non sunt multiplicanda entia praeter necessitatem.

Arneb. That's my answer...Arneb. You're the only phenomena that ties the GDR's need to a natural situation in Kona.

Other wild swings....

The green flash is noted at sunset from the western shore, but that doesn't fit.

Fishing. The GDR may require fishing where those in Kona have natural phenominal fishing.

Mountain observatories, but Kona isn't on a mountain top, I don't think.

Will this effort stir you to say something? [hint]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Just a shot in the dark...does it have something to do with turning off street lights, or making sure all lights are shielded from pointing up?

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I was just sitting here contemplating the immortal words of Socrates who said, "I drank what?"

"Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot." --Carl Sagan "Pale Blue Dot"

A "Shot in the dark" in the best of senses , kelfazin.
It's not quite that, but your answer is taking the right direction.

And George, thanks for your strike. My head still hurts . But I am not that vain. Oh, and I never said anything about the phenomenon in Kona being of natural origin.

When I wrote "Kona", that was pars pro toto. It applies to the rest of the island, too, especially where people dwell.

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Non sunt multiplicanda entia praeter necessitatem.

How about something to do with the mountains, such as places on the roadway, or on top, for observation?

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

Observation is a good word here, but I still favour Kelfazin's approach.

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Non sunt multiplicanda entia praeter necessitatem.

Hm, everyone turns their house lights off? I was thinking the GDR would have that rule due to bombing and Kona due to keeping the skies dark.

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I was just sitting here contemplating the immortal words of Socrates who said, "I drank what?"

"Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot." --Carl Sagan "Pale Blue Dot"