Talk:Tycho Brahe

cites

I have two requests for citation:

the Tychonic system became the major competitor with Copernicanism, and was adopted by the Catholic Church for many years as its official astronomical conception of the universe

and

It gained a considerable following after 1616 when Rome decided officially that the heliocentric model was contrary to both philosophy and Scripture

The first quote strikes me as dubious. When has the Catholic Church (or anyone else) ever had an "official" astronomical conception of the universe?

[-- A reply to the question about the Catholic Church's astronomical decrees: I don't know when these decrees were first made, but that they did exist, is clear: one piece of historical evidence is shown in a book published by the French Minim fathers Le Seur and Jacquier (sometimes wrongly described in the literature as Jesuits) in 1742 -- a version of the third book of Newton's 'Principia' with technical and mathematical commentary. They had to include the following disclaimer, referring specifically to their obedience to the church decrees against the movement of the earth:--

"PP. Le Seur et Jacquier: Declaratio: Newtonus in hoc tertio Libro Telluris motae hypothesim assumit. Autoris Propositiones aliter explicari non poterant, nisi eadem quoque facta hypothesi. Hinc alienam coacti sumus gerere personam. Caeterum latis a summis Pontificibus contra Telluris motum Decretis nos obsequi profitemur."

(A scan of this is -- or was -- to be found on Google Books.) Terry0051 (talk) 09:33, 21 October 2008 (UTC)]

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what is the correct pronounciation of his first and last names? Kingturtle 02:18 Apr 14, 2003 (UTC)

I do wish someone would put this information in the article.Dandrake 02:02, Oct 28, 2003 (UTC)

It's pronounced TEE-KOE BRAH. I'd edit the article, but I don't know how to write it the pronounciation "properly." (i.e.: the confusing way)

Tycho's from Scania just like me, and I'd like to say that the E in BrahE is pronounced; more like BRAH-EE. [[User:Sverdrup|❝Sverdrup❞]] 15:37, 4 Sep 2004 (UTC)

I'm from Denmark, and in Denmark/Sweden, at least, Tycho Brahe is pronounced nothing like "Teeko brah-ee". The vowels are way off. If you're interested in the correct Scanian way to pronounce a Scanian man's name, you need to pronounce the "y" like the german "ü", and the "e" in "Brahe" ike the "ur" sound in "fur". In it's entirety, it's pronounced not unlike "Chew-co Brah-ur", with the "ch" sound replaced with a "t". Quinkysan 07:42, 16 March 2006 (UTC)

I am from across the water, Malmoe in Scania, and I must confess that I do not understand and/or recognise anything in your proposed pronounciation. In Scania, Brahe is pronounced "brah-e". Tycho may be more like "Tü-ko". The pronounciation given by you is the danish one. Please also give a reason why this should be used. Mossig 12:28, 16 March 2006 (UTC)

Apart from our "a"'s, Swedish and Danish pronounce the vowels more or less identically. For instance, we both correctly state that the 'y' should be pronounced as the german 'ü'. But when one is writing a simplified pronounciation for English readers, it's nessecary to write something which sounds right when pronounced according to English conventions. Basically, you need to pretend you're an English person hearing the words and trying to spell them using your own language. I am not for a second suggesting that Tycho Brahe is pronounced "Chew-co Brah-uh" read as a swedish or danish word. However, reading those words in English give a reasonable approximation of the danish/swedish vowels 'ü' and 'e'. If an English-speaker reads the pronounciation key "Teeko Bra-he", he will pronounce it in a very odd way. Remember "ee" in English is an 'i' sound in our languages ('week','feet','sleep', etc') and "he" is spoken as "hi" in our languages (the phrase "he sleeps" would be spelled something like 'hi slipps' in our language.) Ask an english person to pronounce "Teeko Bra-hee", and he will say something like 'Tikko Brahi'. Ask him to say "Chewco Brah-huh", and he will say "Tjüko Brahe", which is a lot closer.Quinkysan 06:55, 17 March 2006 (UTC)

Regardless of the wovels, the inclusion of a j in Tjûko is for me totally wrong. It is not pronounced in that way in swedish or in Scanian. The simplified pronounication you give is still wrong, adn furthermore not necessary even to have in the article as there is both a correct phonetical pronounciation and a sound file. And you have still not commmented on why the danish pronounciation should be used in the sound file and in your simplified text version??? Mossig 16:51, 18 March 2006 (UTC)

I agree that the "j" has no place in "Tycho". If you notice, I state on the page that the "ch" sound (to us pronounced 'tj') is to be replaced with a "t" sound - thus getting rid of the "j" sound. The reason for such a trick is that there is no english word that contains the sound we want to sound like "ty". The closest we can get is "chew", which spelled in our sounds would be "tj-y-u". It might be prudent to advise the speaker to shorten "chew" to avoid the "u" sound at the end. There is no difference at all in the way Danes and Swedes pronounce Tycho Brahe. (Except possibly, that swedes emphazise the final "e" a little more.) There is no conflict here. I have not supplied the sound file, and for people without sound cards, I think it is only fair to give them a chance to pronounce the word properly. Neither mine nor yours is 100% correct, but "chew-co", minus the 'j' sound, is much, much better than "tee-koh".Quinkysan 12:36, 19 March 2006 (UTC)

I have not supplied the "Teekoh" pronounciation. I still think it is better than the new one. But I also think that neither shall be given, and only keep the one given after his name in the article. And there is still no input from anybody what pronounciation to give according to wikipdia guidelines: the danish one, the scanian one (no, they are not the same), the english one, or the Latin one? My vote is leaning towards the Latin, as it is how Tycho himself would have pronounced the Latin version of his name.Mossig 18:25, 19 March 2006 (UTC)

Is any of this relevant to how it was pronounced in the 16th century? Or, more to the point, how do scholars pronounce it today? 75.7.58.246 23:42, 1 September 2006 (UTC)

Why is he being referred to as "Tycho", instead of "Brahe"? Pizza Puzzle

It seems to be the convention. The lunar crater named after him is also called Tycho and not Brahe. ....Lee M 01:34, 4 Sep 2003 (UTC)

It was already the convention by 1620; there was a book called the Anti-Tycho, to which both Kepler and Galileo referred. Dandrake 02:02, Oct 28, 2003 (UTC)

It may be something to do with the way surnames worked in Scandinavia at the time. Only nobles had surnames (commoners for example his wife Kirsten had only a patronymic) and the surname belonged to the family. The given name was the part customarily used to identify the person. Which leads me to wonder why do we say Galileo and not Galilei? —Preceding unsigned comment added by 69.0.26.33 (talk • contribs) 04:31, 31 January 2006 (UTC)

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Brachistochrone

Is it true that the brachistochrone was named after Tycho Brahe? --romanm 09:09, Nov 12, 2003 (UTC)

It's from the Greek "brachisto-" meaning shortest. So say the only sites I can quickly find with a derivation. Dandrake 08:37, Nov 16, 2003 (UTC)

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I am shocked that this article contains no mention of Tycho Brahe's pet moose. - McGravin 18:20, Mar 4, 2004 (UTC)

If it's true, be bold and add it. Anthony DiPierro 18:32, 4 Mar 2004 (UTC)

Penny Arcade

I feel the Penny Arcade mentioning isn't suited for the article - it's just a reference on Penny Arcade's side and as such adds nothing to the article. If anything there should be a link the other way! --Lenton 15:41, Mar 30, 2004 (UTC)

I linked this article a while back to the list of Penny Arcade characters, thinking it was a reasonable thing to clarify and redirect to. It was reverted with the comment, revert; no need to crap up a biography with a wordy link to a list of fictional non-notables. Doesn't make sense to me, since Penny Arcade is certainly notable, and by extension, so are its main characters. I'm re-linking, since it seems to me that's the point of {{otheruses}}, but I wanted to mention what was going on in case of further objections or reversions. My position is that it's too small to be worth removing. And if there should be a link in the reverse, make that link instead of destroying one that exists. (I'll add a link here to the Tycho section of the Penny Arcade page.) Dextrose 23:26, 17 May 2007 (UTC)

Scratch, that link already exists. Dextrose 23:37, 17 May 2007 (UTC)

some Tycho References

Here is a reference that not only mentions his pet elk (European elk, called a moose in North America) but also Jepp his dwarf.

• a down-to-earth biography

And here's an engraving of the nova from his own book that would go nicely in the Cassiopeia section:

• engraving of Tycho's nova

-Wikibob | Talk 21:56, 2004 Apr 24 (UTC)

           I agree wholeheartedly

Is it true

That he had a silver nose? What about his propensity to duel, which I think, is how he lost his nose. Help! Xtreme! 23:56, 7 Dec 2004 (UTC)

Apparently, he had both a silver nose and a copper one, and that he carried an adhesive balm touching up his nose from time to time. His tomb in Prague was excavated sometime around the turn of the century, and they found traces of copper around his nasal cavity. The story goes that for day to day wear, Tycho would use the copper nose, but for special occasions, he would break out the silver.

Tycho had a bit of an ego. I gather that he lost his nose in a duel with Norderup Parsberg (sp?), a fellow student, I think in Germany. The dispute arose when Tycho made an astrological prediction about the death of an Ottoman astronomer. When the prediction was made, the astronomer in question had already been dead for a number of weeks, but, owing to the poor communications technology of the 16th century, Tycho had no way of knowing. When it came out, Parsberg made a few jokes around the dorm - or whathaveyou - which Tycho did not appreciate. A duel followed. Tycho lost his nose and history gained an eccentric.

I think this story is covered in the book by Thoren mentioned on the mainpage, but I gather that the origins of the story (as well as the silver nose) are not neceesarily set-in-stone historical fact. -MFELDM - 12:00 EST, Feb 18, 2005

I've heard it argued that if he had a 'better' nose than the copper one, then he would have wanted to have been buried wearing it. But, his prosthetic nose or noses would also have been one of the few things he was legally allowed to will to his wife and children. By requesting to be buried wearing a nose with a lower intrinsic value, he would have been leaving a slightly better inheritance.--Zerothis 17:26, 14 July 2007 (UTC)

Some name the murderer as Kepler?

User:213.65.17.7 on 22:33, 2005 Jan 30 added text that appears unsourced and unreferenced, for example "Some name the murderer as Kepler, but that part is harder to prove 400 years after the fact."

Now, the external link just afterwards makes no such reference to Kepler and only has this weak conclusion:

Even though it cannot be excluded, it is not likely that Tycho was
murdered, but most likely he conducted his own death by using his own
mercury-rich medicines the day before his death. 

Unless "someone" comes up with a source for who names the murderer, the text should be cleaned up, in my opinion. -Wikibob | Talk 01:42, 2005 Feb 14 (UTC)

Agree! The minimum should be some kind of reference that clears up the weasel word "some". Awolf002 16:44, 14 Feb 2005 (UTC)

The "some" is Joshua and Anne-lee Gilder in the book "Hevenly Intrigue". The argument for murder by poison is, IMHO, convincing, convincing. Kepler is in the book put to blame, and is a plausible candidate. But it is hard to prove it 400 years after the fact.

Okay, so how do they measure up in "notablity"? Is their theory discussed in the relevant circles? Just because they publish a book with their theory does not make it a notable one in the historic sense to me. Or did it create a "media-storm" so it is well known? I did not hear of it. Awolf002 01:14, 29 Mar 2005 (UTC)

I did. The book got press coverage. And please define "relevant circles". The research in Tycho Brahe is not big enough that it warrants its own departments. Most is published as articles and books. The discussion in the book builds upon results on tests on Tychos hair that was made with state of the art techniques at universities. (The theory of poisoning is at least more plausible than the old legend of the ruptured bladder, which is doubtful if it is a medical possibility.) But I am not sure how Wiki defines which sources to believe. The text right now presents the different theories behind Tychos death, which is a good solution, IMHO.

OK. So I removed the reference to Kepler, as it evidently did not fit with the accepted history according to Wiki. But before you remove the reference to poisoning, please tell me why. And please also tell me why the book by Gilder is not allowed in the reference part. The book is the latest about Tycho Brahe, and is well written and well referenced. And I have not seen any one that have questioned the reasoning in it. You can always discuss blaming Kepler, but the argument for murder is good, and well worth mentioning in Wiki.

Reference: www.tychobrahe.com , the homepage of the museum of Uraniborg, says on its web site: "He might have taken it himself as a medicine for his illness. He might have been deliberately poisoned. It is impossible to know for sure. It can only be concluded that he mercury poisoning might have caused his death."

Yes, this is better. I do not question the findings of mercury, just the conclusion that Kepler is somehow involved. That, from the above discussion, does not seem a well founded or widely excepted enough view. Thanks for the references! Awolf002 14:53, 29 Mar 2005 (UTC)

This is in a way getting stupid: now the text about Tycho knowing that mercury in some forms and dosis was harmful, but that it was not in other forms and dosis is questioned. If the editor "Curps" had read the books in the "further reading" section, or even read Tycho himself, he would know that this was the case. When I read wikipedia it is not obvious that all statements should be clearly referenced: much of the rest of the text about Tycho is not. And that includes parts that are not exactly precise: there is no Copenhagen sound for instance. (The name is Öresund). But I do not have the energy to correct these parts if I will have to fight this much over every detail, details that I have references for in my library and that are clear if you have read the books at the end of the article. When Tycho explicitly tells us that he has found a way of making mercury more safe, and that some forms are very dasngerous, I think that warrants mentioning. He did not go around eating mercury at every oppertunity. The poisoning theory is also very old, it has been reported that there were rumours when he died about it, and that was the reason behind that the speach at his funeral detailed exactly what he was supposed to have died from. Maybe (probably?) due to political reasons.

Elk test

I'm glad someone's added the story of his elk, and I've made a few changes to match some web references:

He also had a pet elk, which he cherished. One night during one of Tycho's wild parties, his elk drank too much strong beer, and fell down the stairs. It was killed instantly. After this day, Tycho was never the same.

changed to

Pierre Gassendi wrote^[1] that Tycho also had a tame elk, and that his mentor the Landgraf Wilhelm of Hesse-Kassel asked about an animal faster than a deer. Tycho replied writing there were none, but he could send his tame elk. When Wilhelm replied he would accept one in exchange for a horse, Tycho replied with the sad news that the elk/moose just died on a visit to entertain a nobleman at Landskrona. Apparantly during dinner the elk had drunk a lot of beer and fell down the stairs, and died.^[2]

and footnote 1 is http://www.nada.kth.se/~fred/tycho/nose.html and footnote 2 is http://www.nd.edu/~kkrisciu/strange/strange.html.

According to Amazon.com there is a Dover Publications (1963) edition for footnote 2 (but amazon has had errors before, especially with used books) with an ASIN: B0007DO9CU, but no ISBN. Another reference to the elk, not included in the article is:

• The Search for Tycho Brahe's Nose, a transcription of a paper in the Annals of Improbable research, details: Tycho had sent the elk (called a moose in the paper) to Landskrona to entertain a friend (Prince Wilhelm IV?), according to Pierre Gassendi in 1654.

-Wikibob | Talk 14:17, 2005 Mar 31 (UTC)

That elk story has made my day Murray.booth 11:49, 2 November 2006 (UTC)

NPOW?

Trying to learn how to write wiki-articles. Curps added the last sentence in "He is universally referred to as "Tycho" rather than by his surname "Brahe". Apparently his contemporaries did so and the usage has persisted." as a "clarification". Is this to be considered a NPOW?

(Facts about the name is that is was for a long time the custom in scandinavia to refer to people by their christian name. This goes for everybody, from farmers to kings, as far as I know. Not htat it matters in the discussion of the NPOW.)

Crystalline spheres

I am removing the following text from the article:

This system is frequently described as a "compromise"; however, both the heliocentric and geocentric theories relied upon "crystal spheres", to which the planets were attached. Tycho's theory abandoned the crystal spheres, a remarkable step to take before Isaac Newton formulated the concept of "action at a distance". In this respect, then, the Tychonic universe was more revolutionary than the Copernican.

Galileo had no use for crystalline spheres. (Well, he used the idea in a satirical answer to people who insisted that the Moon was perfectly smooth despite his observations; perhaps that shows his opinion of the whole idea; perhaps not.) And Kepler's elliptical orbits really didn't fit on spheres. Without the spheres, these heliocentrists had no adequate physical theory for why the planets moved as they did: just like Tycho, and everyone else before Newton.

Perhaps Tycho deserves great credit for being bold enough to propose a system that was incompatible with crystalline spheres. Something like that might be put back in the article, without the false invidious comparison to heliocentrism. I don't know for sure whether it's warranted, and don't have any citations to back it up or attack it; someone who knows and has the citations might do the job. --Dandrake 03:21, Jun 8, 2005 (UTC)

I think that the text should be left in. You should add "contemporary" to the heliocentric and geocentric theories. I am not sure about to what extent Galileo theorized aout the crystalline spheres, but both his and Keplers theories was developed _after_ the death of Tycho Brahe. Two of Tychos great insights, and the reason for the fame of his book "de Nova Stella", was that he proved that the new star appeared outside the path of the moon, in the area considered perfect and timeless at that time. Furthermore his measurements on comets showed that the path of these cut through the spheres of the individual planets, contrary to conventional wisdom at that time. (-I do not really understand the ethics of changing Wikipedia articles: as you dont have any references to refute the position you erased, why did you then erase it? Shouldnt you research the area first? I am holding my selfimposed ban on editing this article until I get a better understanding of this. References for my argument above can be found in "de Nova Stella" and in any of the multiple books on Tycho Brahe.)

It's fairly difficult to get a page reference for where Galileo didn't talk about crystalline spheres in the heliocentric system. That is, if Galileo made no use of crystalline spheres in his masterwork laying forth the heliocentric system, then the whole Dialogue is a reference. Seriously, if someone claims to have found a place where Galileo relied on the spheres, he should note the fact, with a citation.

On the other hand, what you say makes a very good case for a paragraph such as I said (just above) might be warranted, noting Tycho's important innovation in abandoning the spheres.

My objection is just to the claim that the heliocentric system required the spheres while Tycho's did not. In the 16th century heliocentric theory did invoke spheres as a physical explanation of the motions (at least I think it did, not seeing any citation here for the assertion, but I can alway look it up in De Revolutionibus); Tycho quite specifically abandoned the idea; 17th-century heliocentirsm didn't use the spheres; neither of the latter had any real physical theory behind the motions they postulated; Newton fixed everything up. So, to say that both geocentric and heliocentric theories had, up to Tycho's time, relied on crystalline spheres as an explanation: that would quite nicely sum it up. --Dandrake 01:22, Jun 13, 2005 (UTC)

Sorry about the hasty defensive tone of that posting. The query about the ethics is well taken. There is an official policy "Be bold" in editing (there's a page on it somewhere), which is often abused: Don't like something, delete it or replace with its polar opposite; don't like a change, just revert it; never provide an edit summary or a comment on the Discussion page. These are bad methods. (In the tradition of proving that one's government is not as bad as Hitler or Stalin, I can now bask in the confidence that I'm above criticism.)

Actually I saw that paragraph as another partisan debating point in a subject (whatever-centrism) that's permanently full of such stuff. It proceeds from an unsupported assertion that can't be strictly true historically to a dubious value judgment. (Not one shared widely by contemporaries, at any rate.) So I saw it, and considered it a small enough point that one would just move it here and see if there's any problem. Arguably, a stronger action than was justified. Upon reflection, it wouldn't take much change to make the passage above criticism. --Dandrake 04:47, Jun 13, 2005 (UTC)

Thanks for the answer. Copernicus is not my speciality, but I have assumed that he used the spheres, as numerous webpages and books refres to things like his book "On the Revolutions of the Heavenly Spheres (1543)" and says things like: "Aside from this change, most of the book still held to Ptolemaic astronomy — the paths of planets remained circular, and the Ptolemaic spheres were still in place." (f.e.x http://www.loyno.edu/~seduffy/scirev.html and http://academic.brooklyn.cuny.edu/history/virtual/core4-4.htm , the latter which says "Brahe thus junked the idea of perfect circular motion, and the idea of fixed spheres in the heavens." The idea that it was Brahe that removed the spheres from the heavens seems common, at least. Even kepler had the spheres in his earlier works, but (I think) removed them later.

It's a good point. Since I objected to the earlier wording and took out too much, I'll take a shot at writing something that properly credits him for decrystallizing the solar system. It's a candidate for revision, as everything is. (BTW, it would be helpful if you'd get a user name and put the four tilde ~ characters at the end of a post, so we could always know who's who.) --Dandrake 20:11, Jun 24, 2005 (UTC)

• How literally people took the spheres to be is a matter of some historical debate. It is clear, though, that Copernicus took them to be fairly material entities, as did many of his contemporaries. Tycho, however, did not, and make a system which was completely incompatible with a notion of material spheres, which is fairly interesting (most other systems are compatible with being agnostic about the spheres). --Fastfission 16:07, 5 November 2005 (UTC)

I don't think Kepler was an assistant of Brahe as Brahe sent Kepler from his doorstep time and time again.

I Think that most reference works make it clear that Kepler was an assistant to Tycho. WilliamKF 00:46, September 4, 2005 (UTC)

Introduction

Is the notion of that "While credited with the most accurate astronomical observations of his time, he was unable to carry the implications of the voluminous data he collected to its logical consequences" have any basis in history?
Brahe had barely time to generate the enormous star catalogue that he measured. If he would have the mental capacity to also generate a star system that fits these observations must be in the real of pure speculation. That the logical consequences of a certain set of observation is unique is also questionable from a viewpoint of science theory and logic.
And to continue, while not trying to minimise Keplers insight into mathematics, is't the sentence " Johannes Kepler, whose superior mathematical faculty " a bit NPOW for an article about Brahe? And also here, do we have any idea of who was the better mathematician between Brahe and Kepler? Please enlighten me.

Tycho never existed!

An authorative professor on Danish history claims to have found proof of Tycho's existence as a fictional person.

Stephen Schwartz has uncovered a little hoax planned by one famous Dane called Ole Worm. In fact all of Tycho's "alleged" discoveries/inventions/stories are a collaboration between Ole and an Icelandic scholar whose name I can't remember at the moment. I think Arngrímur lærði. Arngrímur lærði (1568-1648) studied at København and that is where he met Ole. Ole is thought to have stolen a lot from Arngrímur.

The reason for the collaboration is the fact that the Danish king was playing power-chess with Iceland and to have Arngrímur release his discoveries would have made them go completely unnoticed. Arngrímur was a altruistic fellow with his studies and didn't care about whose name got the credit. I mean, really, do you think that anyone with a silver nose could exist? I mean come on, that's just stupid.

• Uh, right. --Fastfission 16:02, 5 November 2005 (UTC)

Cute, real cute. Somehow I'm not very convinced since I actually held one of Brahe's books in my own hands around a month ago. Valentinian ^{(talk) / (contribs)} 23:45, 17 November 2006 (UTC)

Most men have a iron heart, why Tycho couldn't have a metalic nose? —The preceding unsigned comment was added by 201.19.179.192 (talk) 23:42, 29 April 2007 (UTC).

Tycho and Kepler

The lines about Tycho not being mathematically sophisticated enough to come to the "logical consequences" of his observations strike me as both ahistorical and false. Tycho did come to conclusions relating to his data but he wasn't trying to do the same thing as Kepler, nor was he taking the observations for the purpose of coming up with a precise cosmological system. Furthermore, Kepler's view of the "logical consequences" could be just as similarly judged as imprecise by a modern standpoint — after all, he couldn't go as far as Newton could, and even Newton didn't go as far as Einstein later did, etc. etc., an essentially presentist reading of the past. I think it should be rewritten a bit to stress exactly what Kepler did with the data and exactly what Tycho was trying to do, as best as is known. --Fastfission 16:02, 5 November 2005 (UTC)

It should also be pointed out that Kepler didn't so much "come into possession" of Tycho's data as stole it after his death. Not that it was against Tycho's will, but it was against that of Tycho's surviving relatives. - Cuivienen 02:57, 24 December 2005 (UTC)

Illustrations

The illustrations need sources cited in their captions, especially the pictures from Tycho's Mechanica. They are not watercolors either - they are prints from either copperplate or woodcut, with hand-applied watercolor wash. They look like copperplates to me but can someone go into a rare book library and find out whether they are copperplates or woodcuts? —Preceding unsigned comment added by 69.0.26.33 (talk • contribs) 04:31, 31 January 2006 (UTC)

According to Ronald Brashear, the Curator of Science and Technology Rare Books at the Special Collections Department of the Smithsonian Institution Libraries, some were woodcut and some wre engravings:

After Tycho's death in 1601, it appears that his heirs sold the Mechanica's woodcuts and copper-plate engravings to the Nürnberg writer and printer Levinus Hulsius. Hulsius printed his edition in 1602 and it is very similar to the 1598 edition except that he did not use as fine a paper, the margins are smaller, and the pages do not have the fine border around the text and illustrations. In addition, most of the 1598 copies were hand-colored prior to distribution.

-84user (talk) 17:13, 24 September 2009 (UTC)

Jester

There is now a mention about the dwarf Jepp being believed to be clairvoyant. Is there any reference to this? Otherwise I vote for removal of the notion. Mossig 00:05, 20 February 2006 (UTC)

It sounds plausible, but I agree, without a reference, it's too out there to keep.--ragesoss 01:13, 20 February 2006 (UTC)

You should not remove the jester called "Jeppe". In the 16 century europe it was actually commen to have dwarfs at courts/museums and "wunderkammer"´s. Tychos friend and student Longomontanus writes about dwarf jester Jeppe that is supposed to be Tychos´ Jester in the 1590s. Jeppe made it into Gassendis biografy. Try reading "On tychos Island" By Christianson page 296. There you will find much more about Jeppe. If we can trust every word of Longomontanus, i dont know. But he spend 8 years with tycho at hven and two years in bohemia. And is almost the main oral source for the daily life on Hven.--Thomaslundjohansen 08:53, 10 May 2006 (UTC)

Sound file

The pronounciation of the name is now examplified with a sound file. What could be debated is the choice of language. It is the Danish pronounciation that is examplified. But Tycho was born and lived in Scania, that is now a part of Sweden. And the language spoken at Tychos time in what was then Denmark, now Sweden, was not Danish, but Scanian. And lastly, the name Tycho Brahe is the latinized version of the name, and thus the most "correct" pronounciation should maybe be the Latin one? Is there any standard for Wikipedia when choosing the pronounciation to examplify? Mossig 11:25, 5 March 2006 (UTC)

It is true that Tycho Brahe came from Scania, but the Scanian language was a dialect of Danish at the time. Scanian language was no doubt a very distinct dialect, but it was Danish, not Swedish. Valentinian ^(talk) 10:11, 22 May 2006 (UTC)

According to the Wikipedia article you reference the Scanian language is regarded as its own language.Mossig 09:00, 9 September 2006 (UTC)

SIL has it's own standards. I was referring to the situation before 1658. It is quite true that the upper stratum in Copenhagen didn't consider it to be proper Danish, but I doubt they would have thought any better of West Jutlandic, South Jutlandic or Funish for that matter. :) Valentinian ^{(talk) / (contribs)} 12:28, 7 November 2006 (UTC)

The same discussion goes for the "simplified" pronounciation: Teeko is at an approximation. Before it is changed some kind of consenus should be had regarding which language to use for the pronounciation of names.

This is the English wikipedia. Therefore, the pronunciation most commonly used by English-speaking people should be included in the article. We do not need to decide what pronunciation is the most "correct" - our role is to describe, not to proscribe. TOf course, the article could also mention pronunciation in other languages if desired.

Such a position is against all practice with similar material. Valentinian ^{(talk) / (contribs)} 12:28, 7 November 2006 (UTC)

Tychos´s Legacy in china

I think it could be fun to make a link to the wiki page about the ancient observatory in Beijing. When you see the picture presented on the page, it is a Tychonic equatorial armillary, arcording to "Needham and Wang 1959" it was erected by Ferdinand Verbies ca. 1674. The beijing observatory is older than Tychos Uraniborg and Stjerneborg, but it was rebuild in after 1669 by jesuit astronomers and chinese craftsmen as a virtual reproduction of Tychos observatories. In beijing you can actualy se most of tychos instruments mentioned in the book "Astronmiæ instauratæ mecanica". se link: Beijing_Ancient_Observatory--Thomaslundjohansen 08:53, 10 May 2006 (UTC)

yes, there should be a link with an explanation that replicas of his instruments are on display. --69.9.29.130 04:28, 28 February 2007 (UTC)

Was Tycho Brahe an amateur

Would it be fair to add Tycho Brahe to the Amateur Astronomers' category on the grounds that he was mostly self-funded? I'm trying to figure out how to frame a History of Amateur Astronomy section in the Amateur Astronomy article, and one idea is to pick out a collection of well known astronomers from history who essentially funded their own work. I think Tycho Brahe would fit this, even if he did hire people to help him. Izogi 20:43, 13 July 2006 (UTC)

No. Tycho was funded by the Danish king, and it may even be fair to name Uranienborg on Hven as the first state-sponsored research institute. (I have not researched this topic, there may be older ones. But it is one of the first in europe at least.)

Good point and thanks. I'd forgotten that Tycho was funded specifically to do what he did (and neglected to check the article). Somehow I'd thought he'd just funded the whole thing himself. I guess not. He might still be worth a mention for some of the assertions he made on his own about the supernova beforehand. Izogi 05:49, 16 July 2006 (UTC)

yeah he was

Tycho Brahe's Mars Observations - plot

Note: I posted this over on the Kepler page, but haven't gotten a response yet. It would be nice to include a plot of Tycho's data Kepler used in formulating his laws. I have the raw data (from "Brahe, Tycho. Tychonis Brahe Dani Opera Omnia (in Latin). Vol 1-15. 1913-1929. Edited by I.L.E. Dreyer.") and created a plot using R (see below). I would like to add some regression analysis in order to highlight the periodic nature of the data. This can be a bit tricky with R for non-linear fits. If anyone knows an easy way, let me know and I can recreate the plot. I can also upload the raw data somewhere, if someone would like it?--Thorwald 21:58, 5 November 2006 (UTC)

I think it would be more interesting (and more worl involved) to plot this data in comparison with the predictions made by a suncentered cirkular universe, an earthcentered circular universe, and an earth-centered elliptical universe. (I have seen this plot once in polish, and it nicely shows that Tycho's rejection of the suncentered circular universe is not without merit. Mossig 13:11, 7 November 2006 (UTC)

Death section

I replaced the unattributed bits: "Tycho may have poisoned himself by imbibing some medicine containing unintentional mercuric chloride impurities. Some have even speculated that..." with an attributed verifiable statement based on the referenced book. Please, if you have other verifiable outlooks on his death, do add them, but not without proper reference and attribution. Dicklyon 01:46, 13 January 2007 (UTC)

The part about him possibly poisoning himself is from the same book, p208. Mossig 13:41, 13 January 2007 (UTC)

True, though Kaempe's 1993 conjecture is pretty much superceded by the newer analyses presented in the book. Seems hardly worth mentioning, but if we do we should put in the actual source and date, since this book just mentions it in passing as a previous interpretation of finding extremely high mercury levels in his hair. Dicklyon 05:58, 15 January 2007 (UTC)

But the conjecture presented in "Heavenly Intrigue" is not accepted as the final word either. One of the latest books published about Tycho Brahe, by the Dansih National Museum toghether with the ongoing (very good!) exhibition about his life and work, does not even mention it! Mossig 10:15, 15 January 2007 (UTC)

And it's not presented as final word, but as "Recent investigations have suggested." We should also present other suggestions, but we need to find them first. Dicklyon 00:08, 17 January 2007 (UTC)

This recent event would seem to make the "not urinating" death more plausible: [3]. I don't think his bladder would have to "explode" for him to die. —Chowbok ☠ 03:46, 15 January 2007 (UTC)

The book explains that the mercuric cloride causes kidney failure, stopping the production of urine, and explaining his inability to urinate in the painful week before he died. It's a great read. Dicklyon 05:53, 15 January 2007 (UTC)

Water poisining does not give the drawn-out illness of 10 days which Tycho was experiencing. (The book is a great read, and makes a compelling case. But it is hard to say that it is conclusive. There are other possible culprits if he where poisoned, and he may still have died from another ilness.) Mossig 10:15, 15 January 2007 (UTC)

Conclusive or not, if we want to represent other theories, we need other sources, don't we? Personally, I thought it was enough for a conviction. Dicklyon 17:19, 15 January 2007 (UTC)

I took out the sentence that starts "Critics of the mercury theory point to the fact that Isaac Newton's hair had many times the mercury level of Brahe's" because the reference did not support any part of the statement. It had nothing about critics, or Brahe, or comparative mercury levels. If someone has info on these critics, or how they compared mercury levels, please do add it back with a ref. Dicklyon 18:51, 16 January 2007 (UTC)

Mossig has removed most of the meat of the Gilder conclusion. Why the reluctance to include material from this recent book, which appears to be the most thorough and detailed study of Tycho's death that is available? What are we trying to balance against it? Dicklyon 22:49, 23 January 2007 (UTC)

In the Kepler article the notion that Tycho was murdered is thought as 'fanciful'. I believe we must have some agreement between the two entries as both pertain to the same encyclopedia. This is the first time I hear about Kepler being a murderer and I confess I'm a bit shocked. I suddenly remembered two other men: Salieri and Mozart. —The preceding unsigned comment was added by 201.19.179.192 (talk) 23:40, 29 April 2007 (UTC).

Dear all: I would like to note that I added today Kepler's account of Tycho's death. I hope it looks okay. It is drawn from Kitty Ferguson's 'Tycho & Kepler' (included in the suggested reading list) who in turn sourced it from volume 10 of Tycho's collected work 'Tychonis Brahe Dani Opera Omni'. I was unsure of how to add the reference notations. Perhaps someone could add it or indicate to me where Wikipedia has such instructions outlined. (BB) —Preceding unsigned comment added by Benjaminbudde (talk • contribs) 04:43, 8 May 2009 (UTC)

Pronunciations in Paragraph 2

I redid the pronunciation key to show actual English pronunciations -- only Danish pronunciations were given.

With all the variants this is impossibly long to include at the start of the first paragraph, per typical Wikipedia style. I had to break it out to paragraph 2. Style will simply have to submit to practicality here.

In general, this is getting to be a problem in many articles, and I think Wikipedia needs a formal "pronunciation widget" section somewhere near the top of articles, rather than continuing to try to do it in running text. Britannica online breaks out pronunciations in this way. Perhaps the widget could "open" with a little arrow, to provide more detailed info.

Other points:

• I eliminated the Danish pronunciation key for the Latinized Tycho Brahe form -- Latinized forms are inherently "internationalized" and should always be pronounced in the local Latin (mis-)pronunciation of the reader.

• I left the Danish pronunciation of the original Danish name Tyge Ottesen Brahe. But -- would a 16th Century Scanian have pronounced his own name in 21st Century Copenhagen Danish??

• I didn't put in an English pronunciation of Tyge Ottesen Brahe as it is never used in English -- and (mis-)pronunciations would vary widely if attempted.

• I removed the .ogg file "Da-Tycho_Brahe.ogg" as I couldn't get it to play and see what pronunciation it is giving -- and I assume it is/includes the Danish-ized version of Tycho Brahe which is no longer given in IPA. Please create (a) new .ogg file(s) of all the variant pronunciations shown if you know how to do that.

• Note that for the American pronunciations American phonetic style is used -- [ai] for diphthong, [o] for [o^u], and British phonetic style is used for British pronunciations.

• Note that the A's used in the English pronunciations are all the correct IPA characters. If you are seeing "a" where there should be "alpha" it is your browser tormenting you (as mine seems determined to do to me). There are highly obscure devoicing diacritics in the Danish pronunciation which may be producing gibberish for you, but should be left in for that posterity which some day will see IPA correctly displayed in a browser.

—Preceding unsigned comment added by 75.6.246.77 (talk • contribs)

1) The ogg file you removed used the standard Wikipedia sound format. If you can't make it work, you need to download an .ogg player. 2) If the "Daninized" pronunciation isn't relevant then neither is the American, British (or for that matter Canadian, South African or Australian). "Tycho Brahe" is a Latin name, but a file made by a next-to-native speaker of Latin would be very welcome. The comment "would a 16th Cent. Scanian have spoken 21th Cent. Danish" is a bit odd. Would William Shakespeare recognize the Queen's English? Probably not, since the English language of his time is closer to what is now American. Tyge Ottesen Brahe was an ethnic Dane, and thus a native speaker of Danish, in his case of the Scanian variety. I disagree with the removal of the .ogg file since its purpose is to show that "Tycho Brahe", for one reason or another, has completely replaced his original Danish name in the modern Danish language. It represents how Danes pronounce the name of Denmark's most famous astronomer, nothing more, nothing less. A soundfile of the Danish pronounciation of "Tyge Ottesen Brahe" would however be a good idea. Valentinian ^{T / C} 22:09, 4 February 2007 (UTC)

An even better idea would be to let a Scanian speaking person make a sound file of the pronunciation of "Tyge Ottesen Brahe", even though 16th century Scanian probably had Ottoson - or something similar (Scanian preserves unstressed vowels better than Copenhagish) - rather than 21th century Modern Danish Ottesen. (In 16th century Standard Danish it seems to have been Ottosøn.)

Jens Persson (193.10.116.24 06:57, 7 September 2007 (UTC))

century

The article begins "This article is about the 15th century astrologer," but Tycho was born in 1546 (the 16th century) and did most of his work in the 17th century.

A bit of contradiction?

The following is written on this page:

"Tycho was the last major astronomer to work without the aid of a telescope, soon to be turned toward the sky by Galileo."

while the Johannes Hevelius article states:

"He (Hevelius) is thus considered the last astronomer to do major work without lenses."

I think that this should be resolved. Since Hevelius clearly did his work after Tycho's death, it would appear that the claim for T. is a bit of an exaggeration. H. did use telescopes, but not for his positional observations. Michael Daly 20:34, 27 August 2007 (UTC)

I think the important thing, that makes it possible for both articles to be correct, is the intrepretation of the qualifier "major". Tycho certainly belongs to the major ones, but H. can be discussed. (And no, I do not want to go into that discussion.) If anything, the claim for H. is weaker, as it is very hard to prove who was the last astronomer to convert to using the telescope. Mossig 12:10, 28 August 2007 (UTC)

It isn't who last used naked eye observations, but who did significant work naked eye. The English astronomers contemporary with H. used telescopic observations (that's what Greenwich Observatory as set up for) and they sent Halley to check out H. since they didn't believe he could do such good work without a telescope (Halley confirmed the quality). We can list the major astronomers by any reasonable definition and H. is the last to do anything naked eye. Michael Daly 15:45, 31 August 2007 (UTC)

Tycho's armillary

Neither the original Wikipedia entry nor the talk page mentioned Tycho Brahe's armillary, the instrument he presumably used for his observations. My recollection from many visits to the Smithsonian during the 1980's is that an "Equatorial Armillary" identified as his was prominently displayed, I think in American History near the Focault pendulum. I also recall that there was information suggesting that the displayed armillary was crucial to the quality of Tycho's observations, which were themselves crucial to Kepler's success because of their quality. To be more exact, my memory is that the information stated that Tycho's observations with said armillary were the most accurate of any prior to telescope based observations.

So why is there nothing about this critical part of his life in the article and why no discussion of it in the talk page? The nose and moose story are amusing, but nearly irrelevant to the scientific issues of how such accurate observations were made. If those observations had been of average or lower quality (for their time), this guy would have been just another nobleman dabbling in astronomy.

For reference, the paragraph below is from the Wikipedia entry on armillary spheres (http://en.wikipedia.org/wiki/Armillary_sphere).

Further advances were made by Tycho Brahe, whose elaborate armillary spheres passing into astrolabes are figured in his Astronomiae Instauratae Mechanica. Armillary spheres became popular in Europe during its Renaissance; the Danish astronomer Tycho Brahe (1546-1601) constructed several such instruments.

An additional reference to the Smithsonian library on this topic is at this link:

http://www.sil.si.edu/imagegalaxy/imagegalaxy_imageDetail.cfm?id_image=3312

It seems obvious to me that some modification is needed here to be complete, consistent, and scientifically accurate.

Bob Harrison74.69.194.171 10:07, 25 October 2007 (UTC)

citations needed

I restored the refimprove tag, but accidentally failed to get my reason in the edit summary. The problem is that the details in the article don't include specific citations in many cases, so it's impossible to tell what points are claiming to be verifiable and which are not. Specific citations would make the article better, and that's what the tag says. Dicklyon 18:02, 1 December 2007 (UTC)

But to what degree do you want citations? Should every sentence that bring forth a fact have a separate citation? I think it is enough that the text confirms to what can be found in the reference books listed at the end, and then mainly Thorens biography. If you have any specific items that you think are wrong, remove them and cite the reason.Mossig 18:06, 1 December 2007 (UTC)

It's not about what's wrong, it's about where to verify. I think a footnote on every substantive paragraph would be appropriate, but I'm not going to push that far. At this point there are only 7 footnote citations, and no clue which statements are supported by the other 7 or 8 sources. The Thoren book you mention is not even listed as a source, just as further reading. The tag is just to remind editors to work on these problems. Dicklyon 23:34, 1 December 2007 (UTC)

Correcting problems with parallax

In its 'Supernova' section the article currently states "Tycho, however, observed that the parallax of the object did not change from night to night, suggesting that the object was far away. Tycho argued that a nearby object should appear to shift its position with respect to the background."

However, this statement is seriously misleading in respect of the phrase I have italicised, since it was daily parallax within the same night Tycho was looking for, rather than annual stellar parallax changing from day to day which arises from the Earth's annual orbit of the Sun, but which he did not believe in since he was a geocentrist, and therefore would not expect. But if the phenomenon were something in the Earth's atmosphere and thus sublunar, then it should have had a greater daily parallax than the Moon. But Tycho found no daily parallax, not even as much as the Sun's, and thus concluded the object was so far away as to be in the realm of the daily rotating sphere of the fixed stars. I therefore propose the following replacement

'Tycho, however, observed that the object showed no daily parallax against the background of the fixed stars within the same night. A terrestrial atmospheric object nearer than the Moon should show a greater daily parallax than the Moon's, which is in the order of 1 degree of arc in six hours. But since it had no daily parallax whatever, not even as much as the Sun that Tycho put at 3' of arc, he concluded the object was so far away as to be in the realm of the daily rotating sphere of the fixed stars.' --Logicus (talk) 19:10, 27 December 2007 (UTC)

In de Nova Stella, and in the danish comments to the 1901 facsimile, it is said that Tycho uses the fixed position to the stars during one night to show that it is further away from the earth than the moon, and the fixedness during a 6 month observation interval to show that it indeed must be on the celestial sphere of the stars, and not on the one of one of the planets. I thus think that your new text is fine. Mossig (talk) 19:37, 27 December 2007 (UTC)

Mossig, thanks very much indeed for this most interesting information and its sources. See my comments in your User Talk --Logicus (talk) 17:14, 28 December 2007 (UTC)

After helpful discussion with Mossig in his User Talk, I now propose the current Supernova section's text "Since it had...background" be replaced by:

'Because it had been maintained since antiquity that the world beyond the Moon's orbit was eternally unchangeable (celestial immutabilty was a fundamental axiom of the Aristotelian world-view), other observers held that the phenomenon was something in the terrestrial sphere below the Moon. However in the first instance Tycho observed that the object showed no diurnal parallax against the background of the fixed stars, implying it was at least further away than the Moon and all those planets that do show such parallax. Moreover he also found the object did not even change its position relative to the fixed stars over several months as all planets did in their periodic orbital motions, even the outer planets for which no diurnal parallax was detectable. This suggested it was not even a planet, but a fixed star in the stellar sphere beyond all the planets.'

NB This requires a weblink to a good explanation of 'diurnal parallax', but which is typically maldefined as caused by a motion of the observer, but which it may not be. Thus Ptolemy observed the lunar daily parallax, but did not conclude the Earth rotates daily, but rather presumed the fixed stars along with the Moon do. Unfortunately the current Wikipedia article on parallax is also typically deficient and misleading in this respect, and requires correction. A simple diagram showing how daily parallax would also arise from a fixed observation position on the surface of a fixed Earth viewing a daily rotating Moon and fixed stars is required. The article is also misleading on stellar parallax, overlooking simple single object parallax, used in the 1830's first confirmations of annual stellar parallax due to the Earth's annual solar orbit by Bessell (61 Cygni) and Henderson (Alpha Centauri), and as opposed to dual object parallax. --Logicus (talk) 19:51, 31 December 2007 (UTC)

Further parallax problems and Longomontanus missing In its 'Heliocentrism' section the article currently states

"Tycho believed in a modified geocentric model known as the Tychonic system, for the same reasons that he argued that the supernova of 1572 was not near the Earth. He argued that if the Earth were in motion, then nearby stars should appear to shift their positions with respect to background stars. In fact, this effect of parallax does exist; but it could not be observed with the naked eye, or even with the telescopes of the next two hundred years, because even the nearest stars are much more distant than most astronomers of the time believed possible."

However, the italicised clauses are seriously mistaken because (i) Tycho did not believe in geocentrism "for the same reasons he argued...Earth". Rather he argued the Earth is fixed at the centre and does not orbit the Sun because there was no observable annual stellar parallax, whereas his argument that the 1572 supernova was a star was that it had no observable daily parallax. And (ii), his argument was not that nearby stars should show parallax against others, but rather that in observations six months apart at the two extremes of the Earth's solar orbit, and thus reflecting its maximum change of position by 2 AU with respect to the sphere of the fixed stars, the angular location of the same fixed star should show a detectable difference. This is called 'annual parallax', albeit in fact semi-annual.

Also the article crucial scientific role of Tycho's assistant and disciple Longomontanus in popularising the Tychonic system in the 17th century.

I therefore propose the following replacement and additions in a section retitled 'Tycho's Geoheliocentrism'.

'Kepler..... heliocentric system. Tycho believed in geocentrism because he held the Earth was just too sluggish to be continually in motion and also that if the Earth orbited the Sun annually there should be an observable stellar parallax at six month intervals in which the angular orientation of the same star changed. But none was observable at the time in the absence of sufficiently fine instruments. This parallax does exist, but is so small it was not detected until the 1830s. But unlike the Ptolemaic geocentric system, Tycho proposed a geoheliocentric system, possibly first proposed by Heracalides in the 4th century BC, in which the Sun orbits a central Earth annually and all the other 5 planets orbit the Sun. But in Tycho's model the Earth does not rotate daily but is static. And another crucial difference between his 1587 geoheliocentric model and those of such as Wittich, Ursus, Roslin and Origanus was that the orbits of Mars and the Sun intersected. This was because he had come to believe the distance from Mars at opposition to the Earth was less than that of the Sun because it had a greater daily parallax than the Sun, albeit he had claimed in a 1584 letter to an astronomer Brucaeus that it was further away at opposition in 1582 because he had observed it had little or no daily parallax, whereby he had rejected Copernicus's model because it predicted Mars would be at only two-thirds the distance of the Sun. <See p178-80 of Dreyer's 1890 'Tycho Brahe'> But having apparently later changed his mind to the opinion that Mars was indeed nearer the Earth than the Sun, with consequentially intersecting Martian and Solar orbits this meant there could be no solid celestial spheres because such rotating spheres could not possibly interpenetrate. Arguably this conclusion was independently supported by the conclusion that the comet of 1577 was superlunary because it showed less daily parallax than the Moon, and thus must pass through any celestial orbs in its transit and would thus be sphere-busting.

But it was Tycho's research assistant and disciple Longomontanus who really developed his geoheliocentric model empirically and publicly in his 1622 astronomical tables. When Tycho died in 1601, his program for the restoration of astronomy was unfinished. The observational aspects were complete, but two important tasks remained, namely the selection and integration of the data into accounts of the motions of the planets, and the presentation of the results on the entire program in the form of a systematic treatise. Longomontanus, Tycho's sole disciple, assumed the responsibility and fulfilled both tasks in his voluminous Astronomia Danica (1622). Regarded as the testament of Tycho, the work was eagerly received in seventeenth-century astronomical literature. But unlike Tycho's, his geoheliocentric model gave the Earth a daily rotation as in the models of Ursus and Roslin, and which is sometimes called the 'semi-Tychonic' system. <It should be noted that mere diagrams allegedly of the Tychonic system would actually be indistinguishable from this semi-Tychonic system, unless they indicated whether the Earth or the fixed stars rotated daily.> As an indication of his book's popularity and of the semi-Tychonic system, it was reprinted in 1640 and 1663. Having originally worked on calculating the Martian orbit for Tycho with Kepler, he had already modelled its orbit to within 2 arcminutes error in his geoheliocentric model when Kepler had still only achieved 8 arcminutes in his heliocentric system. --Logicus (talk) 17:14, 28 December 2007 (UTC)

Fair use rationale for Image:Cosmos Brahe.jpg

Image:Cosmos Brahe.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in this Wikipedia article constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.

Please go to the image description page and edit it to include a fair use rationale. Using one of the templates at Wikipedia:Fair use rationale guideline is an easy way to insure that your image is in compliance with Wikipedia policy, but remember that you must complete the template. Do not simply insert a blank template on an image page.

If there is other fair use media, consider checking that you have specified the fair use rationale on the other images used on this page. Note that any fair use images lacking such an explanation can be deleted one week after being tagged, as described on criteria for speedy deletion. If you have any questions please ask them at the Media copyright questions page. Thank you.

BetacommandBot (talk) 20:34, 13 February 2008 (UTC)

grammar?

Under Danish law, when a nobleman and a common woman lived together openly as husband and wife, and she wore the keys to the household at her belt like any true wife, their alliance became a binding morganatic marriage after three years.

I cannot parse that sentence. Is the wearing of the keys a necessary requirement for the marriage to become binding, or is it a parenthetical comment? However, Even without the keys clause it does not parse.-84user (talk) 21:30, 18 May 2008 (UTC) (corrected -84user (talk) 21:35, 18 May 2008 (UTC))

Astrology copyvio?

I moved the whole Astrology section here, because it is a near exact copy of http://www.hps.cam.ac.uk/starry/tychoastrol.html . The cam.ac.uk claims a copyright from 1999, and this internet archive is from 2001 April, so it looks like wikipedia was a copy from cam.ac.uk and not the other way around. Here is the text I moved from the article, with text added in bold and text skipped in struck-through italics like this.

Astrology

Like the fifteenth centuryfifteenth-century astronomer Regiomontanus, Tycho Brahe appears to have accepted astrological prognostications on the principle that the heavenly bodies undoubtedly influenced (yet did not determine) terrestrial events, but expressed skepticismscepticism about the multiplicity of interpretative schemes, and increasingly preferred to work on establishing a sound mathematical astronomy. Two early tracts, one entitled Against Astrologers for Astrology, and one on a new method of dividing the skyheavens into astrological houses, were never published and are now lost.

Tycho also worked in the area of weather prediction, produced astrological interpretations of the supernova of 1572 and the comet of 1577, and furnished his patrons Frederick II and Rudolph II with nativities and other predictions (thereby strengthening the ties between patron and client by demonstrating value).The horoscope shown here is the nativity of King Christian IV of Denmark, composed by Tycho a few weeks after his birth in 1577. An astrological world viewworld-view was fundamental to Tycho's entire philosophy of nature. His interest in alchemy, particularly the medical alchemy associated with Paracelsus, was almost as long-standing as his study of astrology and astronomy simultaneouslyastronomy, and Uraniborg was constructed as both observatory and laboratory.

In an introductory oration to the course of lectures he gave in Copenhagen in 1574, Tycho defended astrology on the grounds of correspondences between the heavenly bodies, terrestrial substances (metals, stones etc.) and bodily organs (medical astrology). He was later to emphasise the importance of studying alchemy and astrology together with a pair of emblems bearing the mottoes: Despiciendo suspicio (- "By looking down I see upward") - and Suspiciendo despicio (- "By looking up I see downward").." As several scholars have now argued, Tycho's commitment to a relationship between macrocosm and microcosm even played a role in his rejection of Copernicanism and his construction of a third world-system.

---

(Above was moved from Tycho Brahe and marked to show differences from cam.ac.uk page. Note the misleading added text (medical astrology)', and astrology and astronomy simultaneously replacing astronomy) -84user (talk) 22:52, 18 May 2008 (UTC) (The above had been inserted back in this edit from 19 September 2004; The cam.ac.uk page has "This page is Copyright 1999, Adam Mosley and the Department of History and Philosophy of Science of the University of Cambridge. All Rights Reserved." -84user (talk) 23:05, 18 May 2008 (UTC))

Tycho's Geo-heliocentric Astronomy

Here are some of my concerns with readability, but I can only offer poor suggestions for improvements (this intends to explain my adding of the {{copyedit}} invitation).

• After Galileo's 1610 telescopic discovery that Venus shows a full set of phases refuted the pure geocentric Ptolemaic model, it seems there followed a majority conversion in 17th century astronomy to geo-heliocentric planetary models that could explain them just as well as the heliocentric model could, but without the latter's disadvantage of the failure to detect any annual stellar parallax that Tycho and others regarded as refuting it.

I can understand and parse the above sentence, but maybe the reader could be assisted by splitting it as follows?

Galileo's 1610 telescopic discovery that Venus shows a full set of phases refuted the pure geocentric Ptolemaic model. It seems 17th century astronomy then mostly converted to geo-heliocentric planetary models that could explain these phases just as well as the heliocentric model could, but without the latter's disadvantage of the failure to detect any annual stellar parallax that Tycho and others regarded as refuting it.

I am not a copy-editor of any kind, so it is likely it could be further improved.

• The fact of Sizzi's 1613 observations of the seasonal variations of sunspot trajectories across the sun's disc being less well explained if not even refuted by a daily orbiting sun rather than a daily rotating earth may have caused a conversion to geo-rotational geoheliocentric models, although Ursus's and Roslin's geo-heliocentric models had also featured a daily rotating Earth, contra Tycho.

I had to break the above long sentence into more-active components to try to understand it:

The concept of a daily orbiting sun failed to explain Sizzi's 1613 observations of the seasonal variations of sunspot trajectories across the sun's disc as well as a daily rotating earth. This may have caused a conversion to geo-rotational geoheliocentric models. However, Ursus's and Roslin's geo-heliocentric models had also featured a daily rotating Earth, unlike Tycho's model.

Now, I agree that does not read well either, but I am hoping someone can do better.

As to the last two paragraphs, I still find them difficult to parse, but especially this last paragraph:

• Three years after the Principia's third edition and two years after Newton's death, it seems to have been Bradley's 1729 publication of the discovery of stellar aberration as only explicable by the conjunction of the heliocentric hypothesis of an annually orbiting Earth with that of the finite speed of light that finally put paid to all forms of geocentrism and thus completed the heliocentric revolution with the complete conversion from Tychonic geo-heliocentrism to pure heliocentrism thereafter as now empirically established fact.

Could this short sentence be used at the start?

It was James Bradley's 1729 publication of stellar aberration that finally put paid to all forms of geocentrism.

And then the paragraph could continue with details, including the end of Tycho's model?

• Finally, the section is slightly out of order and seems to fit better after "Uraniborg, Stjerneborg, and Benátky nad Jizerou" section. The chronology of the following Astronomy section is also awkward as it starts and ends with Tycho's measurements but has a middle paragraph mostly dealing with how his system was considered after his death. Something needs fixing there but I have no good suggstions. -84user (talk) 19:35, 29 September 2008 (UTC)

Logicus's response: Thanks you very much indeed for this detailedd constructive criticism. If I may summarise, it seems your critical style point is really no more than that the sentences are too long? I agree with you. Thanks for the suggested breakdowns. I shall use them in a rewrite asap.

As for your two points about bad order, I had already clocked them but had not yet identified how best to rearrange or delete things as appropriate. But one main idea I have is to introduce a new subsection 'Tycho's astronomy post-Tycho' starting at the current paragraph "After Galileo's...'., and which should also deal with Longomontanus's crucial definitive contribution.

I suggest the section on Tycho's observatories should come immediately after the 'Supernova' section (retitled 'The 1572 Supernova'), retitled 'Tycho's observatories'.

As for the 'Astronomy' section, I suggest its middle paragraph on the geoheliocentric model be deleted, with any non-superfluous material absorbed into the 'Tycho's geo-heliocentric astronomy' section. And it shoud be retitled 'Tycho's observational astronomy'. Then this section should follow the 'Tycho's observatories' section, or to summarise all this re-ordering more simply, just put the 'Tycho's geo-heliocentric section at the end, with the final section being 'Tycho's astronomy post Tycho

So I propose the following order of sections:

---

The 1572 supernova

Tycho's observatories

Tycho's observational astronomy

Tycho's geo-heliocentric astronomy

Tycho's astronomy post Tycho

- The reception of his geo-heliocentrism

- The fate of his observational data

What do you think of this proposal ?

In fact I propose to move the 'Tycho's geo-heliocentric...' section to the end without more ado at least so we can see how this re-arrangement stacks up.

--Logicus (talk) 17:58, 30 September 2008 (UTC)

Yes, the new order makes more sense.

Meanwhile I just reread the article from Career down through to the end of the first paragraph of "Tychonic astronomy after Tycho". Doing that I saw some places for improvement: jargon that might confuse a reader, such as "daily parallax"; the observatories section omitting Herrevad Abbey, although mentioned earlier; and Adam Mosely's astrology page can cite where alchemy and astrology is mentioned.

I will start by trying to better explain parallax. -84user (talk) 20:29, 2 October 2008 (UTC)

Logicus: OK. I was getting round to attempting the explanation of daily parallax, which is relatively difficult and needs a diagram. But your explanation

"diurnal parallax is that observed change of position of an object against the background stars solely due to the rotation of the Earth throughout one day; objects closer than the Moon would have a larger daily parallax than the Moon, for instance"

is mistaken because it would also be observed if the stars and object rotated daily instead. Your explanation implies daily parallax would prove the Earth rotates, but which it does not prove. The geostatic astronomers Hipparchus and Ptolemy both observed it. Nor does it help when most dictionary definitions of parallax are mistaken in attributing it to motion of the observer, which is not necessarily so. See my discussion of these issues in Section 12 of Talk:Parallax, and especially my explanatory diagram of lunar parallax in the Parallax article to see what you think of it: criticism for improvement welcome.

I am drafting something to put in a footnote, bit ugly at present, but see what you think of it, as follows:

'The daily parallax of planets and moons in the solar system is their daily periodic oscillating change of apparent location relative to that of some star(s) as the planet/moon is seen on the stellar background when both are viewed from the surface of the Earth. Xxxxbit more detail needed here.xxx This oscillating displacement arises from the observer's displacement from the centre of the Earth combined with the daily rotation of the Earth, but is also equally predicted by a daily revolution of the fixed stars and the planet/moon as in geostatic planetary models in which the Earth does not rotate. The daily maximum parallax displacement of the Moon, for example, is almost 2 degrees in 12 hours, that is, roughly four Moon diameters.'

Also put in links to 'Parallax'

--Logicus (talk) 16:22, 3 October 2008 (UTC)

Explaining this while including the geostationary concept is hard, but let me split and change the footnote like this:

The daily parallax of a solar system body is the cyclic daily change of its apparent location against the stellar background when viewed from the surface of the Earth.

Xxxxbit more detail needed here.xxx: maybe that it traces an ellipse offset from the mean "true" position? That the change is additional to the parallax due to orbital motion of the Earth (or instead the solar motion if you are Tycho Brahe) and additional to that of the body?

This daily change arises from the viewer's displacement from the centre of the Earth combined with the daily rotation of the Earth. However, the model of a spherical shell of distant fixed stars rotating daily around a non-rotating central Earth produces exactly the same observation.

Maybe also: Therefore, detection of parallax alone is not enough to reject either model.

The daily parallax of the Moon, for example, covers an apparant distance of almost 2 degrees in 12 hours, that is, roughly four Moon diameters.

And merge the best parts together into a footnote. -84user (talk) 21:04, 6 October 2008 (UTC)

Main article's mention of Newton's view is misreported

The main article says that Newton was "studiously no more than Tychonic geo-heliocentric". But that is quite wrong: whoever produced the accompanying quotes from the Principia simply did not read far enough. Book 3, Propositions 11 and 12, go farther than just stating the sun to be at rest, they say it is the common centre of gravity of the sun and planets that is to be considered at rest. This view of Newton's goes back to 1685 and the 'De motu corporum Liber secundus" which preceded the Principia, where he says (in the 1731 English edition) that " ... though the Sun, according to the various situation of the planets, is variously agitated ... with a slow motion, yet it never recedes one entire diameter of its own body from the quiescent center of the whole system." This is Copernican, with added recognition that the sun is almost but not exactly at the center of gravity of the solar system. 92.237.108.47 (talk) 11:46, 21 October 2008 (UTC)

No, it is you who did not quote far enough, omitting the following clause in italics:

"studiously no more than Tychonic geo-heliocentric in its declared six established astronomical phenomena in the preliminary 'Phenomena' section of Book 3""

which is true. --Logicus (talk) 19:29, 22 January 2009 (UTC)

Tycho's daily parallaxes?

Logicus to 84user: I agree with the spirit of your 'Supernova' section 'parallax' clarification request, which is as follows:

"Clarify for which planets Tycho was able to detect the daily parallax with his one minute of arc accuracy. Best Mars oppositions would have 0.7 arcminutes (42 arcseconds), and Venus oppositions would be 1 arcminute. The other planets have parallaxes surely not detectable at that time." Note: 42 should read 26, and 1 arcminute should read 30 arcseconds, as explained below. 84user (talk) 21:19, 6 October 2008 (UTC)

However, on the quantitative details, Dreyer reports that the maximum Martian parallax is 23" at opposition. Thus what is your source please for 43" ?

And what is your source please for a max Venusian parallax of 1 degree ?

I read the contemporary solar parallax measure is some 9" or so. But the ridiculous black hole at the centre of Tycho's data was that he never measured solar parallax and just accepted the traditional Ptolemaic value of 3 arcminutes, thus significantly undermining his proclaimed 'restoration of astronomy' in respect of all other estimates that relied on this fundamental measure.

If Tycho's max observational accuracy was no greater than 1 arcminute, if indeed it was even as good as that, this of course means he cannot have detected any significant parallax for any body other than the Moon and possibly Venus. The great mystery here is why such as Copernicus, Rheticus and Tycho in 1584 thought they detected Martian parallax bigger than solar parallax. The bizarre issue of Tycho's crucial volte face over the 1582 Martian parallax or not requires more detailed discussion, especially of Kepler's critical discussion of it and Kepler's own estimate of Martian max parallax.

Perhaps also see my corrective discussions of parallax issues in Section 24 of this Talk page, 'Correcting problems with parallax'.

--Logicus (talk) 13:58, 5 October 2008 (UTC)

daily parallax 42": My source for 42" (arcseconds) is pure Original Research, and also very wrong for Tycho's location. I calculated it for an equatorial location (and then forgot), but also used rounded figures. 47" is the parallax for an equatorial location at the very best Mars opposition. It should be 26" for Copenhagen or Hven, and 30" for Benátky nad Jizerou. But. Those figures are for the ideal case: best Mars opposition which occurs only every 15 years; a northern winter opposition between March and September; and an ability to measure Mars close to the horizon (less important for mid-winter oppositions). Dreyer probably used good sources and properly accounted for all this. (see below for details)

Ignore my Venus parallax of one arcminute as it was equatorially based; it should be about 30 arcseconds.

These corrected figures make it yet more difficult for Tycho to have measured those parallaxes. Is Tycho's Mars data available online in any form?

Solar parallax: I make the Sun's parallax 17.83" at the equator and 10" at Hven. (12756 / 147,537,780) radians in arcseconds They may mean the deviation from the mean position, which would be just under 9" at the equator.

Ok, I have just seen that German has Horizontalparallaxe which is 8.794" for the Sun and means the observed displacement due to the distance of an observor on the Earth's surface from the Earth's centre. So, someone at the North Pole would see the Sun 8.794" below its "true" position, someone at the South Pole would see the Sun 8.794" above its true position, someone at the sunset terminator would see the Sun 8.794" west of its true position, and so on. That makes 17.588" in total. But daily parallax varies from 8.91" (double to get 17.83") at the equator to zero at either pole. -84user (talk) 23:27, 5 October 2008 (UTC)

As to why Tycho never measured solar parallax, I can only speculate. One can measure the position of a stellar object at night using a clock to record the time between it crossing the instrument's "gnomon" (or whatever it's called) and the time a known reference star crosses the "gnomon". Choose a well-observed reference star that will soon cross the instrument's meridian line. You want to minimise this time gap because the spring clocks used at the time (I don't believe they had pendulum clocks yet) lost accuracy over time. One arcminute at the celestial equator passes in four seconds. If your clock loses or gains up to four seconds after one hour, your measurement error will be likewise plus or minus one arcminute. If Tycho measured the Sun an hour before sunset (not too close otherwise uncertainties in his refraction correction get large) he would need to wait maybe two hours for the first usable star to appear, while the clocks steadily lose accuracy (say plus or minus two arcminutes). Then repeat the exercise before dawn (time the last star, wait two hours, time the risen Sun). This easily produces combined errors of several arcminutes. Venus gives a similar difficulty (unless he made daytime meridian measurements?).

However, it's simpler to measure stars and planets at night because plentiful reference stars are always about to cross the gnomon: time unknown object, wait a few minutes, time known star. After 7.5 minutes the same clock may have lost half a second, which translates to a quarter of an arcsecond, now much smaller than Tychos' claimed observational error of plus or minus one arcminute. Repeat on the next star to cross and cross-check all the derived positions against each other. I could speculate further that if he repeated the measurements of a planet (say Mars) every hour (either moving the instrument or moving to a different instrument) he could combine multiple measurements to reduce the uncertaintity (which he did attach to each value).

daily parallax details: (see below) I just worked out that 23" would have been the parallax for 1578 September at Hven. The 1576 July opposition was 20% closer but poorly placed (-25 degrees declination). The 1580 November opposition is further at around 81 milion km, so a Hven parallax of 18" (but excellent viewing opportunities). Parallaxes get steadily worse: at 1582 December (1584 letter to Brucaeus?) it is 16"; at 1585 late January it is 14". It then gets better until 1593 August when it is around 26". 1595 October has 20". 1600 January would have seen another distant opposition with parallax of just 14".

How I calculated this: Earth's diameter is 12756 kilometres and the closest Mars oppositions have been around 56 million km (0.37 of an AU). Mars Oppositions shows they cycle between 0.38 to 0.68 (almost 102 million km) and back over a 15 year period. One of the closest was in Tycho's time: on 1561 August 7 Mars was only 55,837,780 km away. Oppositions occur at intervals of 26 months. 1561 is similar to the 2003 Aug 28 opposition which was only 0.1% closer and 21 days later in the year. Parallax for an equatorial location is the ratio "(12756 / 55,837,780) radians in arcseconds" or 47 arcseconds. But Tycho was at Hven at latitude 55 degrees 54 arcminutes, not the equator. So multiply 47 by the cosine of the latitude: cos(55 degrees 54 minutes) * 47.12 gives 26.4 arcseconds. I got subsequent opposition distances by extrapolation and repeated. I noted when diurnal parallax would be further reduced due to low declination - I guess by about 13% for summer solistice dates - but did not attempt this adjustment.-84user (talk) 22:41, 5 October 2008 (UTC)

Thanks a lot for all this. Will study it. Meanwhile see memo I sent to Mossig at User Talk:Mossig today, drafted before studying your info. Did you get chance to look at problem of explaining parallax ? --80.6.94.3 (talk) 18:06, 6 October 2008 (UTC)

I am reading Dennis Rawlins' Tycho's 1004-Star Catalog: The First Critical Edition which makes me suspect my example clock inaccuracies are still too accurate for the 16th century, and gives me hints on some of Tycho's methods and errors. It should be clear that errors of position and parallax are not at all constant and vary greatly depending on object and method. As to the parallax footnote - I dissected and rewrote it above. -84user (talk) 21:04, 6 October 2008 (UTC)

Logicus: For possibly getting Tycho's Mars data, see Thorwald's contribution above in section 'Tycho Brahe's Mars Observations - plot'.

Your detailed parallax researches are most interesting. At the end of the day I suggest we need to know two data sets for improving the article, namely Tycho's parallax values and also contemporary values for Hven or wherever at the relevant times. crucially for the Moon, Mars and the Sun and any for the 1577 comet. And also perhaps what values Kepler used. But it seems to me there is thorougoing confusion in the literature about what happened to Tycho's (planetary) data. How can both Kepler and Longomontanus possibly have had it ? etc Photocopies ? --Logicus (talk) 17:58, 8 October 2008 (UTC)

Needs expansion

Compared to the German wikipedia article at de:Tycho Brahe, this English article looks in need of expansion.

I think these areas could be usefully expanded, but I am too lazy to start this!

• Tycho's instruments. See de:Tycho Brahe#Das Instrumentarium and Talk:Tycho Brahe#Tycho's armillary, starting with the quadrant he made in 1567 and maybe also including Wesley's 1979 study of the accuracy of several instruments
• Rudolphine Tables. Or mention them in connection with Kepler?
• Legacy or honours? Convert the Tycho Brahe#Named after Tycho section into prose?
• List of his works. See de:Tycho Brahe#Werke

-84user (talk) 23:37, 2 October 2008 (UTC)

Good points, lazybones (-: The Danish version is surprisingly brief, but at least has two good pictures that should be imported, of 1572 SN and of Tycho's quadrant. --Logicus (talk) 14:02, 5 October 2008 (UTC)

Spelling

The word ""encicle"" appears in the paragraph entitled "Tychonic astronomy after Tycho". This might be an actual quotation.

I fixed it. Dicklyon (talk) 01:35, 14 December 2008 (UTC)

References in Popular Culture

A few things:

1. The title. "Named after Tycho Brahe" is limited, and not all of the items are specifically about naming. The name "References in Popular Culture" is more appropriate, and in line with how articles do it.
2. In articles and literature, when speaking about someone, you usually only use their first and full names once. After that, you use their last name only.
3. I added a source for "The Old Astronomer to his Pupil". However, did you even look for sources before removing the items you removed? That would be preferred over removing them wholesale.
4. Your repeated use of the word "garbage" to refer to others editor's contributions seems to suggest assuming bad faith. Just please try to assume good faith of other editors in the future. Rwiggum (^Talk/_Contrib) 23:43, 12 December 2008 (UTC)

My responses follow your numbers, I hope:

1. Titles with "in popular culture" are trivia sections that attract junk. See WP:TRIVIA and WP:POPCULTURE. It appears that maybe you want to change it so that you can mention "The Old Astronomer to His Pupil," which is a use of his name but is not something named after him. I'd prefer to keep this section more narrowly defined, so that such trivia don't have a place.
2. Read the article where it says He is universally referred to as "Tycho" rather than by his surname "Brahe".
3. No, I remove unsourced trivia rather then spending time to make up for the lazy editors who added it.
4. I'm not assuming bad faith on the part of editors who add junk, but trying to point it out to htem.

OK? Dicklyon (talk) 16:29, 13 December 2008 (UTC)

Honestly, who the heck cares if "Named after Tycho Brahe" is limited? One of the valuable things about Wikipedia is that you can get from it to other resources on the web. Since you've removed the "Named after Tycho Brahe" section, there's a ton of useful links missing. So, get off your high horse and add the section back! (Paul, 29 Dec 08. From Copenhagen!)

The problem is not so much that it is limited but that it isn't. A complete list of everything named after Tycho would take up a disproportionately large part of the article, so if we want to keep such a section here, it would need to be based on some objective selection criteria and so far we haven't got any. If you think this stuff is important, would you be interested in starting a separate list article, say List of things named after Tycho Brahe or Cultural depictions of Tycho Brahe? In a separate list article it wouldn't be a problem at all if the material took up more space. (If someone starts such a list we will obviously add a link to it in the main article.) Hemmingsen 08:46, 30 December 2008 (UTC)

He may be referred to as Tycho, but that doesn't change how things are traditionally written. Also, just because it has "in popular culture" in the title doesn't mean that we can't still police obviously useless additions. Some of the things may be useful. I'd like to get some other opinions on this as well so we can have a clearer consensus one way or the other. Rwiggum (^Talk/_Contrib) 18:30, 13 December 2008 (UTC)

"References in popular culture" is certainly not a perfect title, because stuff like the crater on the Moon won't fit in, and in my humble opinion the crater really is important. Also, while I'm not familiar with Max Brod's writings, I suspect a case can be made that they are more accurately described as high culture than as pop culture, and I don't think we want that to be a reason for exclusion. Hemmingsen 20:26, 13 December 2008 (UTC)

Generally, "popular culture" is a general term when used in instances like this, not just things that would be on Best Week Ever. That would include more "high" culture entries, as well as scientific entries. —Preceding unsigned comment added by Rwiggum (talk • contribs)

I know that the term is sometimes used in a way that distinguish between pop and high culture. I do however consider that to be a somewhat informal or colloquial use which I'd rather avoid in formal writing, mostly because the word popular doesn't convey any information in that case. And to use it in a way that includes references outside cultural works, well, that just seems even less formal. Am I getting that wrong? Hemmingsen 22:20, 13 December 2008 (UTC)

You haven't said explicitly, but sounds like you believe that it is good to put a mention of that poetry into the article. I personally don't see what it adds to an article on Tycho to list every mention of his name. What criteria would you suggest? Dicklyon (talk) 01:37, 14 December 2008 (UTC)

I don't see what mentioning that poetry adds to the article either, and I would actually prefer not having a list here at all. I wrote up a proposal for a legacy-section to replace the list. Objections, criticism and revisions to that section are welcome. Hemmingsen 11:25, 14 December 2008 (UTC)

It doesn't say He is universally referred to as "Tycho" rather than by his surname "Brahe", except in wikipedia sections on pop culture. Why would you want to assert "how it's done" in your experience in conflict with how it's done with Tycho? Who's next? Galileo? Phong? Dicklyon (talk) 01:28, 14 December 2008 (UTC)

You misunderstand. I don't mean what people refer to him as, I mean general stylistic guidelines for formal writing. For instance, news writing, which shares much in common with the style of writing found on Wikipedia. After you mention someone's full name once, from that point on they are referred to by their last name only. This is more formal than using their first name. For instance, we wouldn't say "John Lennon was an English rock musician. John, along with Paul McCartney formed The Beatles." Instead, you say "Lennon, along with Paul McCartney formed The Beatles". In fact, Wikipedia backs me up. If you take a look at the Wikipedia:Manual of Style (biographies)#Subsequent uses of names, it says that "After the initial mention of any name, the person should be referred to by surname only, without an honorific prefix such as "Mr", "Mrs", "Miss", or "Ms"." Also, the Wikipedia Manual of Style for trivia sections also states that "Not all list sections are trivia sections. A trivia section is one that contains a disorganized and "unselective" list. However, a selectively populated list with a relatively narrow theme is not necessarily trivia, and can be the best way to present some types of information." I think that applies in this case. So long as we keep the section policed fairly regularly, there is nothing to suggest it will grow out of control by any means. Rwiggum (^Talk/_Contrib) 02:30, 14 December 2008 (UTC)

Also, your example of Phong is a poor one, since Phong is indeed his lasts name. Rwiggum (^Talk/_Contrib) 02:31, 14 December 2008 (UTC)

Ah, right you did originally say last name, not surname. Bad example then, except in that it illustrates another pattern. A Chinese name like Mao would have been a better example then. I hope you can see that one at least as contradicting what you're saying. Each name has to be considered within the appropriate culture. Anyway, the policy snippet does contradict your "last name" statement, so Phong was a good example against that policy, as as Tycho. You didn't bother to quote the other nuances there, none of which are right on, but that's why the article specifically mentions how he is named in writing about him. Dicklyon (talk) 02:42, 14 December 2008 (UTC)

Wikipedia books

I just noticed the "Create a book" that appears on the left navigation bar allows logged in users to assemble books from a set of articles. Help:Books states that the function is being tested, so just for fun I created Wikipedia:Books/Tycho_Brahe titled Tycho Brahe's life and work.

It's only ten articles, and it is not possible to add images or articles from other wikis. However, I'm thinking of creating some User-space gallery pages to include some nice Commons images of Tycho's instruments. The book is available for editing by anyone (even logged out users). 84user (talk) 08:16, 2 March 2009 (UTC)

File:Tycho Brahe Wikipedia book.pdf is the latest output from Wikipedia:Books/Tycho Brahe : it has 35 pages with 4 page appendix of images from Commons. 84user (talk) 16:31, 2 March 2009 (UTC)

Tycho

Tycho seems to have been the first to cast doubt on the honesty of Ptolemy. This could be mentioned in the article. —Preceding unsigned comment added by 86.137.170.8 (talk) 09:56, 25 April 2009 (UTC)

results from readability and other tools

Out of curiosity I ran article Tycho Brahe through a few Toolserver tools.

• readability: 5021 prose words and reader age of 17+ (Fry index 15).
• find dead links - I fixed a few
• find ambiguous wikilinks - I fixed them
• Traffic reported "Tycho_Brahe has been viewed 27453 times in 200905."
• edit history shows about 500 edits per year, so 1 edit per 50 readers?

I noticed the webchecklinks was reporting [4] as dead but it seemed fine to me. However, WebCite was unable to archive the timesonline link, so I added a note to look for a longer lived cite, as it will likely succumb to linkrot. 84user (talk) 06:53, 29 May 2009 (UTC)

The accuracy of Tycho's observational astronomy and its significance

The first paragraph of the article’s section ‘Tycho’s observational astronomy’ appears to have numerous problems.

The current claim that Tycho's planetary observations were "consistently accurate to within about 1' " is surely false if this means Tycho's estimations of temporal planetary positions. For his most cosmologically crucial estimation of all, that of Martian parallax in its 1582 conjunction, was out probably by as much as 4', inasmuch as he eventually estimated it as greater than solar parallax that he mistakenly put at 3', reportedly simply following Hipparchus rather than doing any observations for himself. Surely the relative consistent accuracy/reliability of a set of astronomical estimates/predictions should not be identified with the greatest accuracy achieved, but rather with the least accuracy consistently achieved. I propose this claim should be replaced by something like the more modest neutral claim that although SOME of Tycho's planetary position estimates were accurate to within about 1', other crucial estimates such as that of Martian parallax at opposition in 1582 were out by 4' or more, and so the overall consistent reliability of his planetary position estimates may be no more than 4'+. --Logicus (talk) 16:40, 25 August 2009 (UTC)

This entire discussion suffers from logical incoherence, as it appears to confuse observations (i.e., pure observational data) with estimates and predictions, which are based on the interaction of observational data with theoretical models and are an entirely different thing. Please read the secondary literature more carefully before removing comments based upon it. --SteveMcCluskey (talk) 19:46, 25 August 2009 (UTC)

Logicus to McCluskey: No, as I understand it, surely it is the article's paragraph itself that suffers the logical incoherence of confusing estimates and predictions of celestial positions with observations, rather than my discussion, which rather seeks to eliminate that apparent confusion.

This confusion seems evident in the following passage, in which a claim about 'observations of positions', which can surely only mean statements or estimations of positions based upon observations, is immediately followed by a claim about planetary observations, which for logical continuity must surely mean observations of positions, as follows:

"his observations of stellar and planetary positions achieved unparalleled accuracy for their time. His planetary observations [of stellar and planetary positions ?] were "consistently accurate to within about 1'," "

For it is difficult to make any sense of 'observations of positions' unless it means 'statements of positions'. Otherwise what would pure data of planetary positions consist of in your view ?

And the same confusion also seems evident in the following passage

"...the stellar observations as recorded in his observational logs were even more accurate, varying from 32.3" to 48.8" for different instruments,[24] although an error of as much as 3' was introduced into some of the stellar positions Tycho published in his star catalog..." [My itals]

What sense is to be made of this passage unless the phrase 'stellar observations' means 'stellar positions' ? For otherwise is seems chalk is invalidly compared with cheese here. Why compare a 3' error in stellar positions with a 32.3" error in stellar observations, unless these two magnitudes are for the same thing and so whereby the former is being said to be much bigger than the latter, rather than being incomparable, and hence whereby the latter phrase must also really mean stellar positions ?

Or are the limits of the precision of instruments being confusingly malcompared with errors in estimated stellar positions in this passage? (i.e. is Wesley's article The Accuracy of Tycho Brahe's Instruments about instrumental error, whilst Rawlins' is about errors in stellar locations ?) On your interpretation surely what we need to know here is what the error was in the stellar observations on which the 3' erroneous stellar positions were based. Were they within 32.3" to 48.8" ?

Is this passage saying Tycho's observational log was much more accurate than his star catalogue ? If so, what is the yardstick against which the accuracy of the stellar observations (i.e. pure stellar data in your view?) in the observational log are being measured ? And what is the yardstick against which the accuracy of the stellar positions in the star catalogue are being measured ? Is the latter maybe nowadays contemporary accepted values of their positions ?

I also point out that the analyses of the accuracy of Tycho's star catalogue by Thoren 1989 and also Hoskin 1999 tend to support my hypothesis that 'stellar observations' in the above passage means 'stellar locations'.

What does it mean for pure data to be accurate or inaccurate in themselves ? Surely data are just data, which cannot be said to be accurate or not unless they are interpreted as representing something else.

To perhaps help sort this disagreement out, in the first instance, in observance of Wikipedia Verifiability etiquette would you please kindly provide the quotation from the Journal for the History of Astronomy article cited that you think verifies the claim that "[Tycho's] planetary observations were "consistently accurate to within about 1',[23]" ", when 'observations' means 'pure planetary data' as you claim ? This may at least clarify whether this apparent confusion is actually in the 'verifying' article, or has been introduced by Wikipedia.

Re your editorial comment, "Undid revision 309999203 by Logicus (talk) per the source you removed which was accurately quoted (consider reading WP:NOR)) (undo)" , please note that the quotation did not itself include any reference to "planetary observations", thus not in itself verifying the Wikipedia claim made.

For the record, the replacement text I edited which you reverted was:

"Tycho was the preeminent observational astronomer of the pre-telescopic period, and his estimates of stellar and planetary positions achieved unparalleled accuracy for their time. Some of Tycho's planetary position estimates were accurate to within about 1', but other crucial estimates such as that of Martian parallax in 1582 were out by 4' or more, and so the overall consistent reliability of his planetary position estimates cannot be more than some 4'+. The stellar observations as recorded in his observational logs were even more accurate, varying from 32.3" to 48.8" for different instruments,..."

Further to this I have drafted the following provisional replacement for the current passages on the star catalogue accuracy.

'The maximum accuracy of Tycho's estimates of the positions of stars published in his star catalogue was even greater than that of his planetary estimates, to half a minute or so for some of its reference stars.[p101 Hoskin 1999]. But the maximum inaccuracy of many of the stellar positions he published in his star catalogue was as much as 3' or more, due to his use of an erroneous ancient value of solar parallax due to Hipparchus that he used as a reference for stellar positions, and also due to his neglect of atmosphetic refraction.[25]. So overall Tycho achieved little better accuracy in his stellar astronomy than in his planetary astronomy, and for a similar reason.'

However, I am currently reviewing whether his max inaccuracies in celestial positions were not in fact far greater.

I do hope you will agree that at the end of the day it is the overall consistent standard of accuracy of Tycho's estimates of celestial locations that is of primary importance in evaluating the accuracy achievement of his observational astronomy. The degree of instrumental precision/error of his instruments is irrelevant to the accuracy of observations in locating a body if, for example, in his absence Tycho's observers were all drunk, the drunken moose ran amok and damaged all the instruments, and they were pointing at the Moon rather than Jupiter whose position they were supposed to be locating.

I do hope that together we can perhaps constructively sort out what the accuracy of Tycho's estimates was from what seems to me the highly confused and apparently conflicting dog's breakfast the literature makes of it. In this context I note Swerdlo commented in Walker 1996 p209 "Various statistical evaluations of his observations have been made, with different results..." --Logicus (talk) 17:20, 26 August 2009 (UTC)

Two points:

First, and least importantly, you objected to my edit to this article, which reverted your text, and to the associated comment. I did not make that edit, which was made by User:77.215.191.91 who can be shown by a Whois check to be from Denmark. It's not me.

Secondly, your proposed text does not make clear the distinction between the accuracy of Tycho's observations (of planetary and stellar positions) and that of the final estimates (both the estimate of Martian parallax at opposition and the estimates of the positions in the star catalog).

It will be helpful if (1) you made clear to the reader the basis and nature of Tycho's estimate of Martian parallax at opposition (I suspect it's a theoretical value, not an observational one) and (2) found an authoritative source on the representative accuracy of Tycho's star catalog and cited it, rather than selected outliers from the data. --SteveMcCluskey (talk) 18:21, 26 August 2009 (UTC)

Steve, apologies for identifying you with User:77.215.191.91 and for your advice on its geographical origin. Now I suppose the Vikings have it in for me (-:

Thanks for your comments, but I don’t understand the distinction you make between the accuracy of observations and of position estimates. You seem not to have read nor understood my criticism of this distinction. For example, the observation that a star is seen at an elevation of 45 degrees above the horizon at some time is neither accurate nor inaccurate, but just an observed fact or not. It is the conclusion that the star is itself located at an elevation of 45 degrees that can possibly be inaccurate, by virtue of atmospheric refraction e.g. So could you possibly please give me an example of what you mean here ?

And I do cite a source on the accuracy of Tycho’s star catalogue, namely Hoskin 1999.

And your removal of my request for the verifying quotation overlooks the point that the quote marks exclude the term "observations" within them, and therefore it does not verify Gingerich and Co were making this claim about observations, rather than positions. OK. SO I restore the flag.--Logicus (talk) 18:19, 27 August 2009 (UTC)

What Hoskin says "[In compiling his star catalogue] First he [Tycho] and his teams determined the positions of selected 'reference' stars as carefully as possible, and then they measured the positions of other stars relative to appropriate reference stars. The accuracy of the catalogue therefore depended in the first place on the positions of the network of reference stars, and by the late 1580s Tycho had determined their positions to within half a minute or so of the true values. Yet although the places of the brightest of the non-reference stars are accurate to around the minute of arc that was his standard, the fainter ones are less accurately located, and there are many errors."--Logicus (talk) 16:27, 28 August 2009 (UTC)

Steve, thanks for providing a verifying quotation from Gingerich & Voelkel 1998 ? I suppose the next question is whether it actually means observations rather than positions, given the literature tends to confuse the two. But if it is about the accuracy of observations in your view, does that article also make any evaluation of the accuracy of Tycho's planetary positions as well as that of his planetary observations ? It is after all the calculated positions that are more important.

And would you care to give your evaluation of the relative accuracy of Tycho's planetary positions and stellar positions ?--Logicus (talk) 14:42, 29 August 2009 (UTC)

Logicus to McCluskey, or anybody: What does 'Tycho consistently achieved an accuracy of observations to within 1 arcminute' mean ? That at some specified time a celestial object could be seen on a line of sight defined by some longitude and latitude angles for some terrestrial location defined by its longitude and latitude such that any difference between that line of sight and the corresponding line of sight specified by Tycho was never more than 1 arcminute ? Or were the observations only of the latitudinal and longitudinal angles between the object and some reference star(s) at some location at some time ? --Logicus (talk) 14:30, 30 August 2009 (UTC)

Hi Logicus,

In your earlier note, you suggested that it is the accuracy of the calculated positions that are more important. I'd have to disagree for several reasons:

• First, the section is titled "Tycho's observational astronomy." Clearly for that section it is his observed, rather than calculated positions that are more important.
• Second, from a historical perspective, Tycho's observed positions were used by Kepler in the work that led to his Astronomia Nova, and the accuracy of those observations sheds light on the validity of Kepler's concern over the famous 8 minutes of arc discrepancy that led him to an elliptical orbit.
• Finally, the section does go beyond the raw observations to discuss the reduced observations (I prefer that term to the ambiguous calculated positions) that appear in his star catalog.

In your more recent note, you seem to be confusing terrestial latitude and longitude, which measure positions on the earth from the equator and the prime meridian, with celestial latitude and longitude, which measure positions on the celestial sphere from the ecliptic and the first point of Aries. Position on the Earth can be ignored for most of Tycho's observations. The only role of position on the Earth in Tycho's observations would be to convert observations related to the local vertical to observations related to celestial coordinates; those observations measuring distances between celestial bodies would not require position on the earth at all. (the diurnal parallax for the sun and planets are measured in seconds of arc, and are too small to be detected by Tycho's instruments). --SteveMcCluskey (talk) 16:21, 30 August 2009 (UTC) edited 17:38, 30 August 2009 (UTC)

Thanks. Will comment on this later. But immediately could you possibly please answer the question I posed of what a Tychonic 'observation statement' consists of, whether innhis star catalogue or planetary observations log, and with respect to what yardstick it may be said to be relatively accurate/inaccurate. Surely such things need to be made clear to the reader trying to learn something about this subject ?--Logicus (talk) 17:59, 1 September 2009 (UTC)

Hello Logicus,

I'm wondering based on some of your comments how much do you understand about observational astronomy and what difficulties would you experience in making an astrometric catalog using late 16th-century technology. You seem capable of writing a lot, but I ask this to determine what you actually understand. That would help me to answer any confusion. --Dgroseth (talk) 05:31, 2 September 2009 (UTC)

Dgroseth,

I share your puzzlement with Logicus's latest comments. The sentence presented in the main article speaks for itself, assuming one is familiar with the difference between the concepts of accuracy and precision. --SteveMcCluskey (talk) 14:38, 2 September 2009 (UTC)

Logicus to McCluskey:Your reference here says

“In the fields of science, engineering, industry and statistics, accuracy is the degree of closeness of a measured or calculated quantity to its actual (true) value. “

So in that case that sentence would be saying Tycho’s measurements of planetary positions were consistently accurate to within 1’ of their actual value = actual positions ?

This is what I originally suggested it meant, but you denied that..--Logicus (talk) 18:23, 3 September 2009 (UTC)

What is the relevance of Tycho's measurement of Earth's axial tilt ?

The article currently claims

"For example, Tycho measured Earth's axial tilt as 23 degrees and 31.5 minutes, which he claimed to be more accurate than Copernicus by 3.5 minutes."

But what on earth (pun intended!) is this measurement an example of ? The immediate context of the preceding sentence makes it read as though it is an example of errors in stellar positions in the star catalogue discussed immediately beforehand, but yet which it is obviously not. So is it an example of the accuracy of Tycho's planetary observations to consistently within 1 minute proclaimed in the second sentence of this paragraph? But it clearly does not provide any such example because (1) the Earth is not a planet in Tycho's astonomy, and (2) telling the reader Tycho claimed his measurement was more accurate than Copernicus's measurement(?) by 3.5 arcminutes does not tell us whether or not it was accurate to within 1'. So is it an example of how his observations of stellar and planetary positions achieved unparalleled accuracy for their time, proclaimed in the first sentence of this paragraph ? Again obviously not, since this measurement is not about the Earth's position, which Tycho placed at the centre of the universe, also making the Earth completely immobile with no axial rotation. In conclusion, this whole sentence seems to be entirely irrelevant as an example of any claim preceding it. I request clarification of its relevance, or else its deletion.

Moreover, insofar as Copernicus made no observations as many claim and never published any observational astronomy, then it seems Copernicus’s value here may well not be an observation, but rather the actual value of the tilt he gave in De Rev. Thus this sentence may confuse observational measurements with real values. And if Tycho measures the tilt as 23 degrees and 31.5 minutes, then his measurement was some 5 arcminutes in error compared with what I understand to be the modern real value of 23 degrees 26.3 minutes.--Logicus (talk) 17:57, 3 September 2009 (UTC)

The sentence about axial tilt has been around since (at least) 2005 without any documentation to support it; I've changed your "clarification needed" tag to "citation needed". I've removed your other "clarification needed" tag about precision as it was explained above. --SteveMcCluskey (talk) 20:49, 4 September 2009 (UTC)

Tycho's value of 23°31.5' is given in Albert Van Helden, Measuring the Universe, pp. 91-2. Your comparison of it to the modern value of 23° 26.3' assumes obliquity is constant; it isn't. Modern formulas give a value of about 23°29.5' for the obliquity in 1600. Van Helden attributes the remaining discrepancy in Tycho's derived value to Tycho's difficulties incorporating solar parallax and refraction into the analysis of his solar measurements. --SteveMcCluskey (talk) 00:19, 5 September 2009 (UTC)

Logicus to Steve McCluskey: Thanks for this and the info on history of this sentence. I am of course aware of the variable obliquity. So on the analysis you present here, it seems Tycho’s error would have been some 2.5’ if he measured it in 1600. So on that basis I reckon he was probably even more inaccurate than Copernicus by some 1.5’ rather than just by 1’ on the basis of my following analysis, drafted before I read yours. But then my estimate of 1600 obliquity is 36” less than yours. And Copernicus (1525?) at 23d 28.5m is only about 0.5' out and De Rev value of 23d 29m is virtually spot on your 1600 value of 23d 29m 5s.

I propose to go ahead with deleting the sentence for same reasons stated below. I hope you agree, unless of course you can provide some better analysis that extracts some relevant point out of this dog’s breakfast.

---

Predraft

Logicus to Mc Cluskey: I propose to delete this bizarre sentence for the following reasons. It seems the only sense to be made of it is that it is a botched attempt to at least illustrate, if not demonstrate, an implicit thesis unstated here, namely that Tycho achieved unparalled accuracy in his ascribed celestial positions for his time. And it apparently seeks to illustrate such superior accuracy by comparison of Tycho's value for the Earth's axial tilt - the angular orientation of the Earth's polar axis to the polar axis of the plane of the ecliptic - with that of Copernicus. But it appears to be botched even as a non-probative illustration of the superior accuracy of Tycho's values for celestial positions for the following reasons.

First note that the sentence only reports that Tycho claimed to be more accurate than Copernicus by 3.5', but not that he actually was more accurate. But it is the truth of Tycho's relative accuracy that is important here, not what Tycho claimed it was. So what is the truth ?

In De Revolutionibus [p559 Britannica Great Books 16], Copernicus gave the value of the obliquity of the ecliptic as 23 degrees 29 minutes. According to Pannekoek 1961 (p212), Tycho's value of 23d 31.5m was 2' too big. Thus apparently Pannekoek took the true value to be 23d29.5m whenever it was that Tycho measured it. Now if this were also the true value for whenever Copernicus put it at 23d 29m, then Copernicus's value would have been more accurate than Tycho's, with an error of only 0.5' compared with 2' for Tycho.

However, I do not know when Copernicus and Tycho made their measurements, and thus what the true values of the secular variable axial tilt were at those times. We may speculate that Copernicus's value of 23d 29m in De Rev was intended to be that at the time of its publication. But Pannekoek (p197) tells us Copernicus measured it to be 23d 28.5m in 1525, and gave it as 23d 28m in De Rev (whereas, admittedly in haste, I read him as giving it as 23d29m in De Rev) . Pannekoek also claims Walther measured it, like Copernicus, to be 23d 28m, but fails to say when Walther measured it. Presumably not 1525. As for Tycho, my calculations of the axial tilt in 1600 based on a value of 23d 26m 21s in 2000 and an annual decrease of 0.5" arcsecs per annum put it at 23d 29m 41s that year, only some 11" difference with what Pannekoek took its true value to be when Tycho measured it, which was presumably sometime between 1580 and 1600. Thus it seems fair to conclude Tycho's value was in the order of 2' in error as Pannekoek reports. But it also seems fair to conclude Copernicus's value was at most not much more than 1' in error, and hence probably more accurate than Tycho's by some 1’.

But as a mere layperson, I hand over to experts in medieval astronomy such as McCluskey and Dgroseth for further comment, and hopefully to learn what the truth of this matter might be.

However, I delete the claim because of its apparent confused irrelevance within the current text, and because it seems so dubious that Tycho's estimate of the axial tilt was more accurate than Copernicus's. But I offer the following constructive suggestion.

There are two separate issues raised here. Was Tycho's astronomy more accurate than Copernicus's ? and Was Tycho's astronomy the most accurate for his time, say for the 16th century ? On the first question, we read that Tycho set about the renovation of astronomical accuracy because the Ptolemaic Alfonsine Tables and the Copernican Prutenic Tables were in error by 1 month and 2 days respectively in their predictions of the 1563 Jupiter-Saturn conjunction. Thus one centrally much more appropriate measure of whether Tycho's astronomy achieved greater accuracy than Copernican astronomy, or indeed than Alfonsine, would be the accuracy of his predictions of Jupiter-Saturn conjunction, if any. But hereby hang tales of their highly anomalous conjunctions from Kepler to Newton and beyond....

On the wider question of whether Tycho's astronomy was the most accurate in the 16th century, Regiomontanus and Walther seem to be likely fellow contenders. However the highly confused and conflicting literature on Tycho's accuracy reveals that the key problem here is determining a scientifically valid overall citerion of accuracy, rather than indulging in the bad habit of citing the odd value here and there that was more accurate than another astronomer's corresponding value. The two main contenders are surely that of the maximum deviation of the whole set of values from their actual values at the time according to modern reckoning, and that of their least mean deviation. Both are useful, but the former arguably more important. Such evaluations may reveal some interesting historical surprises.--Logicus (talk) 14:54, 5 September 2009 (UTC)

It's not just accuracy

Although accuracy is a major part of Tycho's contribution, equally important is his extensive and systematic program of astronomical observations and the way that they contributed to Kepler's theoretical work. The game of seeking the most accurate astronomer of his time is not very enlightening; what we really want is the astronomer who had the most significant influence on the astronomy of his time. In looking for historically significant astronomers, we need to consider the accuracy and extent of an astronomer's observations and their influence on his contemporaries and successors. --SteveMcCluskey (talk) 22:48, 5 September 2009 (UTC)

Logicus to McCluskey: I don't understand what your point is here, or what proposition your are talking to, albeit I largely agree with it, except for the view that Tycho's most important historical contribution was that of his data to Kepler's theoretical work. Rather I regard the contribution of his cometary data to the dissolution of the celestial spheres along with his mistaken value for Martian opposition parallax and the influence of his planetary model as the prevailing 17th century model as far more important. The dissolution of the solid spheres, involving all the planets, was by far the most important development in 17th century astronomy, making the heliocentrism v geocentrism issue relatively trifling. And on Rheticus's analysis in the first Copernican publication it was of course their presumption combined with the belief that Martian opposition parallax was greater than solar parallax that necessitated a heliocentric planetary model as the only physically possible model. This of course belies the silly nonsense that Kepler introduced physics into astronomy and initiated celestial physics.

However, I did not introduce the issue of Tycho's relative accuracy into the article anyway. Was that not you ? Are you now implying it should be removed ?

On the issue of looking for historically significant astronomers, with respect to the 16th & 15th centuries it was arguably Regiomontanus because of his introduction of Arabic trigonometry into Latin astronomy, if it is true as I have seen claimed that this is what enabled accurate measurements of parallax that became so cosmologically crucial in Tycho's hands.

On the issue of the identifying the historically most significant pre-telescopic astronomers for the extent of their influence and relative accuracy, I reckon Hipparchus is the main contender, possibly along with the Babylonian astronomers whose secular data so impressed Eudoxus and Aristotle, and also Ptolemy, pace Robert Newton. Hence I strongly disagree with this paragraph's opening claim that "Tycho was the preeminent observational astronomer of the pre-telescopic period". Since the claim is unsourced and anyway contentious, I propose it should be deleted as adding nothing positive to the article and simply raising a probably undecideable contentious issue.--Logicus (talk) 18:21, 7 September 2009 (UTC)

OK, I see you're still trying to advance your reinterpretation of the astronomical revolution against the consensus of mainstream history of science. You may think that the view that Kepler introduced physics into astronomy and initiated celestial physics is "silly nonsense", but it can be documented by innumerable secondary sources. If you can provide sources that explicitly reject that consensus, please cite them. Do not, however, expect other editors to give much credence to extensive quotations of primary sources accompanied by your own unique syntheses.

I'll grant you the small point that Hipparchus, the Babylonians and Ptolemy have a claim to the "most significant," but an assertion of the historical significance of Tycho's observations belongs in the article, and I will rephrase it citing an appropriate reference. --SteveMcCluskey (talk) 20:03, 7 September 2009 (UTC)

But could you please expain what the following claim means: Tycho's observations of stellar and planetary positions were noteworthy both for their accuracy and quantity.[23] His "planetary observations [were] consistently accurate to within about 1'," " for the layperson ?--Logicus (talk) 18:19, 8 September 2009 (UTC)

No, I do not intend to continue participating in your filibuster. Perhaps others may wish to engage in your perpetual debate, but I do not. I will continue to edit the articles on my watch list. My edits will reflect valid criticism, but I will not engage in further debate. --SteveMcCluskey (talk) 22:48, 8 September 2009 (UTC)

Sorry you lost your rag (-: ! No filibuster intended. There is a serious confusion in the literature here that needs sorting out for the layreader. --Logicus (talk) 18:27, 9 September 2009 (UTC)

Did Tycho neglect atmospheric refraction or not ?

The article currently claims

"an error of as much as 3' was introduced into some of the stellar positions Tycho published in his star catalog due to his application of an erroneous ancient value of parallax and his neglect of refraction." [My italics]

but also claims

"He was aware that a star observed near the horizon appears with a greater altitude than the real one, due to atmospheric refraction, and he worked out tables for the correction of this source of error." [My italics]

These two claims about Tycho's treatment of atmospheric refraction appear to be inconsistent. What is the truth ? Did he neglect it or not ? Is Rawlins possibly wrong, and the errors only due to error in solar parallax  ? --Logicus (talk) 18:22, 9 September 2009 (UTC)

Rawlins does not verify star catalogue max error claim

The article currently claims

“an error of as much as 3' was introduced into some of the stellar positions Tycho published in his star catalog due to his application of an erroneous ancient value of parallax and his neglect of refraction.[25]”

But the source referenced in p20 n70 of Rawlins 1993 make no such claim. Rather it only claims:

"However, since TB's error[70] in obliquity is +2’, we find that, while many primarily refraction ­caused errors in delta stand uncorrected,....

70 The error introduced, by TB's false oversized (ancient) adopted parallax plus his ignoring of polestar refraction, is about 2'.8, which approximately accounts for the +2' error in his obliquity."

Hence it makes no claim about the maximum error of the 1000+ stellar positions in the star catalogue. On Rawlins testimony it is much greater, at least 6 degrees. I am currently trying to identify the max error he identifies, in pursuance of the apparent aim of this paragraph to identify the consistent accuracy of Tycho’s celestial positions, that is, their maximum inaccuracy. A consistent level of accuracy is defined by the maximum outliers, contrary to McCluskeys advice to exclude outliers.

In the first instance I therefore flag this claim as a failed verification.--Logicus (talk) 16:25, 18 September 2009 (UTC)

So your latest claim is that any stars with total errors bigger that 3' prove that this statement is false:

An error of as much as 3' was introduced into some of the stellar positions Tycho published. - fascinating --Dgroseth (talk) 05:32, 19 September 2009 (UTC)

Logicus to Dgroseth:

No ! But quite funny, smartypants !

However, you completely miss the main issue here, namely that this footnote has nothing whatever to do with stating any error in Tycho's stellar positions, be it a maximum error or mean error or any other stellar position error. Rather it is explaining the error in a terrestrial position, namely explaining Tycho's 2' error in the Earth's obliquity as the product of the error in a 2'.8 'correcting' factor introduced by his adopting the oversized ancient Hipparchan solar parallax value and also discounting polar refraction. So the quoted footnote 70 is not about any error in any stellar positions whatever. Sorry if my comment did not make this sufficiently clear for you, and created the impression that my complaint about this footnote was just that this 3' is a stellar error that is not the maximum stellar error in Rawlins' analysis, rather than not a stellar error at all.

In fact as you may not have noticed, contrary to the claim of this sentence, it seems Tycho never published any star catalogue whatever. So far as I can tell from the literature I have reviewed, the only 'Tychonic' star catalogue ever published was the posthumous publication of Tycho's 777 star Catalogue C, published by Longomontanus, who claimed to have been the supervisor of star cataloguing at Hven. It seems the 1004 star Catalogue D analysed by Rawlins was never published. Why he elected to pour his admirably Herculean efforts into analysing this "error plagued" catalogue rather than the only published one, I can only wonder ?

Correction: If Swerdlow is to be believed, Catalogue C was not the only Tycho star catalogue published. For according to Swerdlow 1996 p210, Tycho himself had circulated Catalogue D in manuscript form, which arguably counts as publication, and Kepler published it in his Rudolphine Tables. This casts a negative light both on the alleged great accuracy of Tycho's publications, and also on Kepler's on Rawlins' report of that "error plagued" catalogue. For if Tycho and Kepler both published it verbatim as now published in Tycho's collected works. including all the errors in that publication reported by Rawlins, even replete with its entirely bogus stars, then they published a catalogue with a max error in excess of 20 degrees and a likely mean error of several degrees. For example, one need only consider the gross total effect on its mean error of the latitude error of some 23 degrees incorporated in each of its 188 southern star latitudes by virtue of its 'typo' (i.e. 'scriberr'?) that misrepresented their latitudes south of the Ecliptic as south of the Equator.--Logicus (talk) 11:27, 24 September 2009 (UTC)

Seriously though, the statement in question is clearly intended to be a statement of the max error of the star catalogue. For if not, then why arbitrarily pick out a 3' error or any lesser error than the max error ?

I therefore propose to delete this entire clause as an unsalvageable and misleading dog's breakfast, pending some reliable objective evaluation of the level of accuracy of the 777 stellar positions published in Tycho's star catalogue C to be gleaned from the literature, if such be possible. I suggest we need to know the max error, mean error and in comparison with the max and mean errors of previous or contemporary star catalogues such as those of Hipparchus and Hevelius. I am currently reviewing the literature to see whether these have been determined. Can you help, or is your intended contribution to this constructive project just that of sniping at Logicus from the sidelines ?

So I propose the following provisional holding clause pro tem:

'But the stellar positions posthumously published in his 777 star catalogue C were far less accurate.'

I do hope you concur.

--Logicus (talk) 21:03, 22 September 2009 (UTC)

"Stellar positions more accurate than 1' " unsourced and mistaken

The article currently claims

"the stellar observations as recorded in his observational logs were even more accurate, varying from 32.3" to 48.8" for different instruments."

and this claim is sourced in a JHA article by a Walter Wesley.

But that article only considers the accuracy of the positions of 20 stars altogether, and is therefore useless for determining the overall accuracy of the 777 star Catalogue C or of the 1004 star Catalogue D, being less than 2% of the latter stars for example.

I therefore delete this claim, as having a failed verification and which anyway seems preposterous.--Logicus (talk) 23:53, 23 September 2009 (UTC)

The myth of Tycho's 1' accuracy ?

The article currently claims

His [Tycho's] "planetary observations [were] consistently accurate to within about 1'."[24]

and its footnote 24 source in Gingerich & Voelkel 1998 JHA says

"[24] We have found Tycho's mature planetary observations to be consistently accurate to within about 1', in agreement with Dreyer's and Thoren's assessments. See Victor E. Thoren, "New light on Tycho's instruments", Journal for the history of astronomy", iv (1973) 25-45, pp41-42."

However, this reference and its footnote has numerous possibly fatal problems that suggest the Gingerich & Voelkel ( and Wikipedia) claim is unreliable and indeed false, as follows:

(1) G & V give no published reference for their alleged finding of the level of accuracy of Tycho's planetary observations, and of their methodology and data source. This is peculiar. So did they really undertake any such independent exhaustive research akin to that of Rawlins? And where is it published, if anywhere ?

(2) The G & V footnote fails to identify what Tycho's mature planetary observations are, as distinct from his immature planetary observations. For example, were his 'crucial' observations of Mars at opposition in 1582-3 mature or immature ?

(3) The G & V footnote notably also give no reference for Dreyer's alleged assessment of the accuracy of Tycho's planetary observations. Is this possibly because Dreyer never made any, but only assessed the accuracy of a limited number of Tycho's stellar positions compared with Bradley's ?

(4) Unlike G & V, Thoren's article does not credit Dreyer with making any proper assessment of Tycho's accuracy, rather than just making an unfounded assumption about it. He simply says "[Dreyer] was willing to assume that [by 1585] the accuracy of roughly +- 1' was typical of Tycho's mature observations."[My itals] But 'typically accurate' can be a far cry from 'consistently accurate' , the far stronger claim made by G & V.

(5) Pages 41-2 of the Thoren article referred to do not make any assessment whatever of the accuracy of Tycho's specifically planetary observations. Rather the article is only concerned, at most, with the accuracy of all his celestial positions in general, stellar, planetary and cometary.

(6) Thoren's article is really only concerned with assessing the max possible reliable precision in measuring celestial astronomical angles that could possibly be achieved by Tycho's instruments, but not with assessing the minimum or mean accuracy of all his actual observations and celestial positions in relation to some yardstick of their 'true' observations or positions. Thus G & V go way beyond Thoren's findings in claiming agreement with any Thoren finding of a consistent accuracy within 1' in Tycho's planetary observations. What Thoren says at most on Tycho's accuracy is this: "[Dreyer] was willing to assume that [by 1585] the accuracy of roughly +- 1' was typical of Tycho's mature observations. For stellar and planetary positions this was probably true, although for some reason in secondary reports of Tycho's work the 4' figure has been cited more frequently than the 1' value."

(7) The fact that Thoren apparently interpreted accuracy of 'observations' to mean accuracy of actual 'positions', and so judged Tycho's 'observational' accuracy to be within 1' of actual celestial positions, and G & V's citation of being in agreement with Thoren about Tycho's accuracy, suggests G & V made the same semantic equation, and so also really meant 'calculated positions' when they confusingly spoke of 'observations'. If so, then their evaluation of Tycho's consistent accuracy in celestial positions was most likely grossly wrong in the light of such as Rawlins' findings of Tycho's stellar position errors,

In conclusion, G & V's claim seems multiply confused, and at the end of the day seems little more than a case of simply uncritically parrotting Tycho's own (now known to be grossly mistaken) claim that he had plotted celestial positions to consistently within 1' accuracy, rather than the result of any serious scientific research into evaluating the relative accuracy of Tycho's estimated celestial positions of stars and planets.

I propose this claim of the accuracy of Tycho's planetary observations be deleted as false, and this whole paragraph be replaced by a scientifically serious analysis of the comparative accuracy of Tycho's celestial positions, if at all possible. But if the academic history of science literature cannot provide such, then maybe this paragraph should be replaced by a report on the gross failings of that literature on this issue. --Logicus (talk) 20:35, 26 September 2009 (UTC)

Gingerich and Voelkel clearly state that their research finds "Tycho's mature planetary observations to be consistently accurate to within about 1'." If you can find explicit sources that state that Tycho's observations did not reach this accuracy, fine; cite them. Please cease your continued practice of placing your own interpretations against the findings of published sources. I am reverting your recent edits. --SteveMcCluskey (talk) 02:12, 28 September 2009 (UTC)

Logicus to McCluskey: Given it is plainly evident from the G & V article and its references, as pointed out in my points 5 & 7 above, that what it means by "planetary observations" is in fact neither 'observations', nor just specifically of planets, but rather 'calculated celestial positions' in general, including both stellar and planetary positions, then many sources that state Tycho's consistent accuracy (i.e. max level of error never exceeded) in celestial positions was very significantly less than achieving +-1' error can be cited. But why bother with what would be a long and tedious resume of the confused and conflicting literature on this issue, recounting all the confusions and conflicting opinions of such as Dreyer, Thoren, Wesley, Gingerich, Voelkel, Swerdlow, Hoskins, Rawlins etc. ? Why not just state the best scientific summary of Tycho's accuracy that can be gleaned from the highly confused and inconsistent literature by the application of common sense and elementary logic to its analysis in order to try and determine the truth of the matter ? This is only what the best Wikipedia editors can do at best anyway in giving their summary interpretations of all the literature, albeit many history of science editors seem to have read very little of it, and elementary logic and common sense seems well beyond them., as may even be English language literacy, as in the case of Dgroseth by his own most admirably candid admission below, for example.

What you are doing in restoring the G & V claim is imposing your own idiosyncratic interpretation of the literature as accurately represented by this G & V claim, but which it is most certainly not.

Contrary to your claim, I do not place my own interpretations against the findings of published sources. Rather I point out the contrary findings of other published sources in what is typically the context of there being no broad consensus, but rather only confused and conflicting opinions, just as I have variously pointed out above. I then attempt a fair NPOV summary of what logical common sense suggests is the likely scientific truth of the matter from the literature. In this particular case, given the G & V finding of the max error in celestial positions conflicts with that of many others and is pretty obviously grossly mistaken (for example, the Rawlins publication on the star catalogue D reveals many errors of many degrees, as much as well over 20 or 30 degrees, if not over 200 degrees), I offered a provisional holding summary in its stead, provisional upon determining an agreeable more specific fair summary of the levels of accuracy of planetary and stellar positions achieved in Tycho's planetary and stellar catalogues /'observations'.

I therefore restore my previous edit, hopefully this time with your agreement that it is a fair holding position in view of all the circumstances I have depicted. For the record it is:

“He aspired to a level of accuracy of within 1', but many of the stellar positions in his star catalogues were far less accurate than that.”

--Logicus (talk) 18:01, 30 September 2009 (UTC)

Hi, Prof. McCluskey, I see your back from the Wikibreak you took from this article. I'm a bit green to Wikipedia and might want help with policy and such. Btw, is asking someone a crude question or making a vulgar remark possibly considered a personal attack?

Regarding this same person and some of his comments on errors and precision:

I'm not quite sure how to parse everything correctly regarding his/her earlier opinion of how Rawlins' and other people's analysis of Catalog D was "the highly confused and apparently conflicting dog's breakfast" and again a few blunders such as misidentification, reading the instruments or poorly written values, or whatever in the data set that resulted in a few stars with errors up to 6 degrees would render it, "an unsalvageable and misleading dog's breakfast".

Wow, I guess I'll tear up my list of Messier objects, and all of those Near-Earth object surveys that are supposed to save us, even the latest have questionable data. It would NOT be logical to save the world without knowing every NEO to some minimum precision. What about the data set consisting of every statement by Logicus, does it have any blunders, and if so, should his/her standard apply to him/her, assuming he/she calls it a blunder?

On further analysis of the Edit history of Logicus, I see this comment to 84user revision as of 11:00, 2009 September 24. It seems like some deleted items were worth keeping after all.

Anyway, lets let bygones be bygones, I'd be happy to start over and discuss the 7 points of Logicus and a few more mentioned earlier, only I won't write as much. I write with a splint quite slowly, and I see Logicus often likes to add 2K text every time, often making several erroneous statements in a single post. If he/she is patient, we can reach some agreements.

I'm a klutz with remembering policy, grammar, spelling and such, although I do understand astrometry quite well in different circumstances, optical and radio, differencing errors and combining different kinds of reference frames.

My first question for Logicus as an authority in astronomy, if I take a photograph of a region of the sky say 30 degrees above the horizon with a few objects with known positions and an object with an unknown position, how big could the photo be before the calculated position error ignoring refraction is 1 arc minute? --Dgroseth (talk) 05:31, 28 September 2009 (UTC)

Hi Dgroseth,

Nice point about the problems with evaluating a survey on the basis of its maximum errors. The studies I've read tend to employ the average error, sometimes after discarding "obvious outliers." Some discussions of robust statistics have proposed using the median of the absolute value of the deviation, which includes outliers but in such a way that they do not have a great influence on the measure or variability.

Given Wikipedia's restrictions on original research, we'll have to go with the statistical analyses found in the published literature on the history of astronomy. --SteveMcCluskey (talk) 15:10, 28 September 2009 (UTC)

Observational logs

I have just restored the passage "the stellar observations as recorded in his observational logs were even more accurate, varying from 32.3" to 48.8" for different instruments." That is exactly what the article cited is about -- see Wesley's discussion of his method (and his critique of those of his predecessors) at pages 42-3, JHA 9(1978). --SteveMcCluskey (talk) 12:30, 29 September 2009 (UTC)

You have apparently overlooked the fact that this article is useless for the purpose at hand because Wesley only considers 20 stars. I therefore re-delete it. Logicus.

Wesley focused only on what could be best reconstructed.

We should be using Thoren 1973 instead of a footnote in Owen Gingerich and James R. Voelkel for footnote 24 along with Wesley for the next one.

Victor E. Thoren, New Light on Tycho's Instruments, 4 (1973) 25-45 1973JHA.....4...25T

Logicus also removed the following half-truth that needs to be fixed before reinsertion into the lead or wherever:

He did what others before him were unable or unwilling to do – catalogued the planets and stars with enough accuracy to determine whether the Ptolemaic or the Copernican system described the heavens more accurately.{{Clarify|date=September 2009}}

In fact, The claims that Tycho makes in his personal correspondence can only make sense if at times believed in a model where the orbit of Mars and the orbit of the Sun do not intersect and Tycho believed the diurnal parallax of the Sun was a measurable nearly 3 minutes of arc as this value was never challenged by Tyhco. That is the heart of the article by Gingerich and Voelkel, so don't toss it.

Owen Gingerich and James R. Voelkel, "Tycho Brahe's Copernican Campaign," Journal for the History of Astronomy, 29(1998): 2-34,

Also note the graphs on page 22 has Tycho's different adopted refraction values. Note that they are different for stars and sunlight. It is reasonable to not think they are the same, when refraction was poorly understood. Unfortunately he was wrong. --Dgroseth (talk) 05:47, 30 September 2009 (UTC)

Logicus to Dgroseth: No doubt due to your admirably self-professed poor literacy, you seem to misunderstand why the Wesley reference given was invalid and so deleted. May I therefore explain its invalidity for you, as follows. The issue at hand as raised by the G & V 1998 quotation was the level of accuracy consistently achieved by Tycho's celestial positions, which is of course measured by their maximum error. But the immediately following clause on the error of Tycho's stellar observations in his observation logs that apparently reports a max error of 48.8" is taken from Wesley's Table 4. But Table 4 does not state the max error, but rather the average error for 7 instruments for only 8 'fundamental' stars. But obviously the max error will be greater than the mean error. And it is apparently to be found in Table 3, as reported by my new footnote 24 as 2' 3". However, even this finding is irrelevant since it is Tycho's general level of accuracy that is at issue here, but Wesley only reports the max error of just 8 stars, which is obviously a wholly statistically wholly invalid of the 1004 stars catalogued. The only valid use that can be found for Wesley in this context is that which I have cited in my footnote because it scuppers the silly claim that the max error of Tycho's celestial positions was +-1'.--Logicus (talk) 14:33, 3 October 2009 (UTC)

Logicus to Dgroseth: Your Edit commentary for deleting my article revision 317492700 -“The WP:SYN removes an important reference while not containing another discussed) (undo)”-

is clearly threefold mistaken.(i)This was not WP:SYN and I challenge you to demonstrate otherwise given your own admission that you do not understand WikiPolicy, (ii) it did not remove an important reference, but rather removed a clearly mistaken and patently fringe view and (iii) it discussed no less than 11 references. May I respectfully suggest you consider whether you are as yet sufficiently literate to be editing an encyclopedia. Please stop your highly confused reversions of my revisions concerned to improve the scientific accuracy of this article. --Logicus (talk) 14:50, 3 October 2009 (UTC)

Yes my eyes glaze over when trying to learn WikiPolicy, and yes I am responsible, even for rules that I don't understand. This is why I am going slow. I can find ways to use references that make Tycho look bad, and I can find ways to use references that make him look better than he was. See Fundamentals of Astrometry, Jean Kovalevsky and P. Kenneth Seidelmann, Cambridge University Press, 2004, p 2,3. Either way compromises the integrity of the article in a way considered synthesis. I do know Tycho discovered the next four previously unknown terms in the motion of the moon, in agreement with what Brown published less than a hundred years ago. Did he consult a mystic or determine them by careful observation? --Dgroseth (talk) 05:26, 4 October 2009 (UTC)

This is irrelevant confused nonsense ! You clearly fail to cite any WP:SYN policy rule that my contribution demonstrably breaches. The issue here is not to make Tycho appear more or less accurate than he was, but just to establish precisely how accurate he was, which is what my efforts are directed towards and towards eliminating the ludicrous mythologizing of his accuracy by some fringe elements. My contribution does not compromise the integrity of the article in any way. Nobody is denying Tycho made careful observations. But what he discovered or not, however worthy, is irrelevant to determining his general level of accuracy. Please stop your invalid reversions. I have restored your last deletion.--Logicus (talk) 14:40, 4 October 2009 (UTC)

I don't actually enjoy reverting an hour or more of work. I think think it would be best to thrash it out calmly on the talk page, one detail at a time. It seems like the axial tilt had its own section once, buried in the middle only to disappear. Wouldn't it be best if it and other issues had their own section? I find some sections to meander quite a bit.

Does a point of view have to be original to qualify for WP:SYNTHESIS? For example, would a series of edits that were pro Flat Earth and the elimination of references against a Flat Earth viewpoint count? I thought the degree of NPOV qualified for synthesis, but I might be wrong. Anyway, I see SteveMcCluskey has done some hard work, with the the result a bit less biased in my opinion. --Dgroseth (talk) 05:00, 5 October 2009 (UTC)

What was the historical significance, if any, of Tycho’s alleged superior accuracy ?

One of the historical fairy tales about Tycho to be found in some of the literature, and which underlies this article's concern with Tycho's accuracy, is that planetary orbits were thought to be circular before Kepler proposed they were elliptical as a result of Tycho's more accurate planetary positions that revealed they were more elliptical rather than circular.

But of course this tale is nonsense from the very outset in its presumption that before Kepler planetary orbits were circular. For as is evident from more intelligent and scholarly aspects of the literature and such as Dennis Duke's animations of geocentric planetary orbits, the historical facts of the matter are that planetary orbits were thought to be non-circular millenia before Kepler, being epitrochoidal around the Earth in such as the Ptolemaic model, for example. They were also non-circular around the Sun in Copernicus's heliocentric model.

The upshot of the influence of this nonsensical tale by virtue of its erroneous presumption that Copernican heliocentrism posited circular planetary orbits is that maybe nobody has ever yet bothered to determine the crucial issue of whether Kepler's planetary orbits were more accurate than Copernicus's or Reinhold's

In the case of pure heliocentric astronomy post Copernicus, key questions that arise with respect to the issue of what contribution, if any, Tycho's planetary positions made to determining Kepler's ellipse hypothesis are as follows. In the first instance we solely consider the paradigmatic case of Mars and Tycho's plots of its orbital positions.

NB Answering these questions may require reference to the Prutenic tables as well as or even rather than De Revolutionibus .

1) What was the path/shape of the Martian orbit in Copernicus's heliocentric planetary model ? Just how non-circular or elliptical/ovoidal or not was it ?

2) What were the max, min and mean deviations of Copernicus's predicted Martian orbit from all of Tycho's plots/predictions for whatever period ?

3) What were the max, min and mean deviations of Kepler's predicted Martian orbit from all of Tycho's plots/predictions for whatever relevant period ?

4) Was Kepler's Martian orbit more accurate or not than Copernicus's or Reinhold's Prutenic Martian orbit according to Tycho's orbital position plots/predictions for some same orbital period, and on what measure ?

5) Was Kepler's Martian orbit more accurate or not than Copernicus's or Rheinhold's Martian orbit for some orbital period according to modern orbital position plots/predictions for that same period, and on what measure ?

6) Was Kepler's Martian orbit more accurate or not than Longomontanus's Astronomia Danica Martian orbit according to Tycho's orbital position plots/predictions for some same orbital period, and on what measure ?

7) Was Kepler's Martian orbit more accurate or not than Longomontanus's Astronomia Danica Martian orbit for some orbital period according to modern orbital position plots/predictions for that same period, and on what measure ?

It should be noted that Copernicus's astronomy was apparently more accurate than Tycho's at least in respect of the Earth's obliquity, an important referential constant in which Tycho was some 2' in error whereas it seems Copernicus was possibly virtually spot on. Hence this does raise the issue of whether Tycho's astronomy was generally more accuarte than Copernicus's.

The overall key issue here is whether Kepler's planetary orbits were any more accurate than Copernicus's or Reinhold's, and if so whether their greater accuracy was in any way crucially enabled by Tycho's observations. There is also the issue of whether Kepler's orbits were more accurate than those of Longomontanus, who also used Tycho's 'observations'.

Contributing editors may wish to help improve the article by detemining such questions. --Logicus (talk) 18:27, 30 September 2009 (UTC)

Try and get your novel ideas about Tycho Brahe published in a peer reviewed magazine before trying to change the Wikipedia article. This is not the place for OR. --Saddhiyama (talk) 20:07, 30 September 2009 (UTC)

Logicus to Saddhiyama:But Logicus has no peers (-: And anyway only in the weird and whacky feudal ivory tower of academia does anybody regard peer review as anything other than a recipe for reactionary corruption by the usual suspects, a paradigm of 'the police investigating the police'(-:

Thanks for this unsolicited advice, but you should consider trying to improve your literacy, for no novel ideas about Tycho Brahe are presented here, and this is not Wiki OR. So may I invite you to provide a demonstration that it is OR, and identify what idea(s) about Tycho presented here you imagine to be novel ?

Perhaps you should read my above apposite comments of 30 September to Steve McCluskey, especially re your deletion of my 30 September article edit, which was not OR as you alleged:

"Contrary to your claim, I do not place my own interpretations against the findings of published sources. Rather I point out the contrary findings of other published sources in what is typically the context of there being no broad consensus, but rather only confused and conflicting opinions, just as I have variously pointed out above. I then attempt a fair NPOV summary of what logical common sense suggests is the likely scientific truth of the matter from the literature. In this particular case, given the G & V finding of the max error in celestial positions conflicts with that of many others and is pretty obviously grossly mistaken (for example, the Rawlins publication on the star catalogue D reveals many errors of many degrees, as much as well over 20 or 30 degrees, if not over 200 degrees), I offered a provisional holding summary in its stead, provisional upon determining an agreeable more specific fair summary of the levels of accuracy of planetary and stellar positions achieved in Tycho's planetary and stellar catalogues /'observations'."

I do not know what ideas about Tycho you imagine to be novel, but it is certainly not the idea that Tycho's observations did not determine Kepler's elliptical orbits. For example, as Curtis Wilson's 1989 article Predictive astronomy in the century after Kepler. wisely says

"Because of the level of unavoidable error in observations of position, and the near circularity of the orbits, the departure from circularity could be detected observationally only in the orbits of Mars and Mercury, where the eccentricity was exceptionally large; and even in these cases the choice between ellipse and other oval shapes was, as far as the observations could show, a matter for conjecture. Kepler, of course, had reasons for his choice: a causal account of which led both to the elliptical orbit and to the planet's motion on that ellipse, with close agreement between the theoretical prediction and observation in the particular case of Mars."

Stop making bogus allegations of OR and stop reverting my edits without demonstrated valid reason ! --Logicus (talk) 16:06, 2 October 2009 (UTC)

I will be answering some of your questions soon. See my comment in the previous section for now. --Dgroseth (talk) 05:21, 4 October 2009 (UTC)

Logicus to Dgroseth: Are you Saddhiyama or replying for them ? --Logicus (talk) 14:25, 4 October 2009 (UTC)

Dgroseth here, not Saddhiyama. I didn't mean to but in on a private exchange, I was interested in the topic. While we are discussing epitrochoids, deferents, equaints and epicycles, I wanted to join if I may. I used to have a spirograph and it was fun. Almagest rules? --Dgroseth (talk) 05:17, 5 October 2009 (UTC)

If you want to do some useful work here, could you possibly determine the shape of Mars' orbit according to Copernicus's De Rev, or find some reference in the literature that states what it is ? And also determine its deviations from Brahe's plots. --Logicus (talk) 17:42, 5 October 2009 (UTC)

Wot planetary parallax observations ?

The article currently claims

"Tycho's naked eye measurements of planetary parallax were unprecedented in their precision - accurate to the arcminute, or 1/30 the width of the full moon."

But to what planetary parallaxes does this refer ? He got the Sun’s parallax wrong by some 3’ and that of Mars at opposition by some 4’. Did he give any values for the Moon, Mercury and Venus ?

This unsourced claim is surely simply grossly false and must be deleted ? Meanwhile I flag it for a source and for clarification. --Logicus (talk) 14:48, 4 October 2009 (UTC)

The article also currently claims

"These jealously guarded measurements [of planetary parallax] were "usurped" by Kepler following Tycho's death."

But this is surely nonsense, even apart from the misuse of the word 'usurped' for the word 'stolen'. For the literature suggests, rightly or wrongly, that what Kepler stole from Tycho's legally legitimate heir(s) was not just whatever records of measurements of planetary parallax he had made, as claimed here, but rather at least all of Tycho's observational data of the Martian orbit, or possibly his data of all planetary orbits, or at most his data of all celestial motions. But which of these he stole is utterly unclear from the literature, even from Dreyer's admirably detailed and fascinating account of the posthumous career of Tycho's records. For example, what Tychonic data did Longomontanus have access to or not in compiling his geo-heliocentric Tychonic Astronomia Danica model of the planetary system that was regarded as the completion of Tycho's astronomical programme of improving the accuracy of planetary motion prediction. And what Tychonic data was he deprived of by Kepler, if any ? Longomontanus had been the supervisor of stellar obsevations at Hven, and posthumously published Tycho's star catalogue, so it seems Kepler did not steal all of Tycho's records. And why did Newton negotiate with Roemer to try and get Tycho's data for publication in Halley's astronomical catalogue in the early 18th century ? It seems incredible that Newton was trying to get data from the pre-telescopic era published with those of the telescopic era.

This unsourced sentence must surely be deleted, and replaced or covered elsewhere by an account of what Kepler actually did steal, and what became of Tycho's records. --Logicus (talk) 17:36, 5 October 2009 (UTC)