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In particular (you can take this as a TL;DR summary), it is about the myth that some people were stupid (for example, to oppose ideas of Kepler or Galileo), whi

In particular (you can take this as a TL;DR summary), it is about the myth that some people were stupid (for example, to oppose ideas of Kepler or Galileo), while others were smart. They were all pretty smart, and the opposition to new ideas actually had math and data (that were available at the time!) on its side. Kepler's model, for example, required a believe in gigantic stars (all starts are the size of Betelgeuse or even larger), based on data available at the time, which today we know was wrong. Somewhere else I read about Galileo, as far as I remember apparently his telescope was pretty bad and it wasn't that other astronomers refused to look through it, as our modern myth about their "stupidity" goes, but that what could be seen was not conclusive. I may be wrong about the last one, this is from what I read long ago elsewhere, the Kepler theory is a main theme in the linked article though. Another document: https://arxiv.org/ftp/arxiv/papers/0903/0903.3429.pdf https://arxiv.org/ftp/arxiv/papers/0903/0903.3429.pdf > How Marius Was Right and Galileo Was Wrong Even Though Galileo Was Right and Marius Was Wrong -- or, how telescopic observations in the early 17th century supported the Tychonic geocentric theory and how Simon Marius realized this. Sometimes scientists who followed their instincts were right, and those who followed the available facts/data were not. Sometimes. Or in other words: Things are not that simple.

mannykannot 8y ago
It should be noted that Brahe's model was not the classical Ptolemaic geocentric / epicyclic model: "It is conceptually a geocentric model: the Earth is at the center of the universe, the Sun and Moon and the stars revolve around the Earth, and the other five planets revolve around the Sun." [1] The Popperian model of science suggests that it steps from one empirically-sound but falsifiable position to another, but that is the view with hindsight - what happens at the leading edge is much more fluid, and having the right sort of instincts about where the evidence is leading is not just a matter of luck. Heliocentricity was generally accepted well before stellar parallax was observed. It appears to me that MOND (Modified Newtonian Dynamics) seems to be going the way of Brahe's model - it fitted the initial data, but does not seem to work consistently for the general case. [1] https://en.wikipedia.org/wiki/Tychonic_system https://en.wikipedia.org/wiki/Tychonic_system
DanAndersen 8y ago
"The Great Ptolemaic Smackdown" [0] also provides information to this effect. Yes, as the link you provide mentions, there's an optical phenomenon known as the Airy disk that suggests an incorrect apparent size of stars when looking through such old telescopes. It wasn't until the 1800s that this phenomenon was understood. [0] http://tofspot.blogspot.com/2013/08/the-great-ptolemaic-smackdown.html http://tofspot.blogspot.com/2013/08/the-great-ptolemaic-smac... (part 1)
- acqq 8y ago
  And still, the whole "The Great Ptolemaic Smackdown" is based on false arguments: The author claims: "the reaction at the time was "WTF? Which heresy are you talking about here?" But the exact heresy was explicitly and very clearly stated both in the sentence by the Inquisition: http://hti.osu.edu/sites/hti.osu.edu/files/documents_in_the_case_of_galileo.pdf http://hti.osu.edu/sites/hti.osu.edu/files/documents_in_the_... "the above-mentioned Galileo, because of the things deduced in the trial and confessed by you as above, have rendered yourself according to this Holy Office vehemently suspected of heresy, namely of having held and believed a doctrine which is false and contrary to the divine and Holy Scripture: that the sun is the center of the world and does not move from east to west, and the earth moves and is not the center of the world, and that one may hold and defend as probable an opinion after it has been declared and defined contrary to Holy Scripture." And in Galileo's Abjuration: http://www.creatinghistory.com/galileo-galileis-abjuration-22-june-1633/ http://www.creatinghistory.com/galileo-galileis-abjuration-2... "after having been judicially instructed with injunction by the Holy Office to abandon completely the false opinion that the sun is the center of the world and does not move and the earth is not the center of the world and moves, and not to hold defend, or teach this false doctrine in any way whatever, orally or in writing; and after having been notified that this doctrine is contrary to Holy Scripture; I wrote and published a book in which I treat of this already condemned doctrine and adduce very effective reasons in its favor, without refuting them in any way" The premise of the whole series by that author is also wrong, approximately, that because the parallax wasn't observed until around 1750 Galileo couldn't prove in 1633 that the Earth is not standing still, therefore the Church was right and it wasn't a matter of faith but a personal thing. It's obviously a completely invalid argument.
Florin_Andrei 8y ago
The epicycle theory was pretty clever and complex, and fully supported by data at the time.
- 8bitsrule 8y ago
  fully supported by data at the time. Not so much; people who -could see- the phases of Venus were in possession of -conclusive- data that it was not moving in a circle between the Earth and Sun. "Although the extreme crescent phase of Venus has been observed with the naked eyes, there are no indisputable historical pre-telescopic records of it being observed." https://en.wikipedia.org/wiki/Phases_of_Venus https://en.wikipedia.org/wiki/Phases_of_Venus There may be no records, but that might not have stopped ANYone with keen eyesight from knowing (including the Greeks back to Aristarchus, or even the Babylonians). For 2000 years, the 'authorities' (e.g. Aristotle) were wrong.
  - Florin_Andrei 8y ago
    No, I don't think that would have been considered solid data in any time period. It's almost the definition of "things only very few people claim to see". There are no records of it from the ancient world, and "Venus with horns" could mean anything. > For 2000 years, the 'authorities' (e.g. Aristotle) were wrong. Careful to not let desires and personal aspirations cloud your judgment there.
gmiller123456 8y ago
The author of that article (Graney) on Galileo's observations teaches at a nearby university, and I was able to attend a lecture he gave about the effect. The tl;dr is that when you look through a telescope today stars are pinpoints. You can magnify them as much as you want, and they still appear pinpoints. Brighter stars might appear larger than smaller ones, but their size doesn't change with magnification. Galileo's telescope had such a small aperture that diffraction distorted the image, and the size of the disk of a star did change with magnification. Since they didn't understand diffraction at the time, they thought they were seeing the star's disk. Since there was no measurable parallax on stars at the time, they knew they had to be very far away, and thus unbelievable enormous in order to have a disk visible in a telescope.

mannykannot 8y ago

It should be noted that Brahe's model was not the classical Ptolemaic geocentric / epicyclic model: "It is conceptually a geocentric model: the Earth is at the center of the universe, the Sun and Moon and the stars revolve around the Earth, and the other five planets revolve around the Sun." [1] The Popperian model of science suggests that it steps from one empirically-sound but falsifiable position to another, but that is the view with hindsight - what happens at the leading edge is much more fluid, and having the right sort of instincts about where the evidence is leading is not just a matter of luck. Heliocentricity was generally accepted well before stellar parallax was observed. It appears to me that MOND (Modified Newtonian Dynamics) seems to be going the way of Brahe's model - it fitted the initial data, but does not seem to work consistently for the general case. [1] https://en.wikipedia.org/wiki/Tychonic_system https://en.wikipedia.org/wiki/Tychonic_system

DanAndersen 8y ago

"The Great Ptolemaic Smackdown" [0] also provides information to this effect. Yes, as the link you provide mentions, there's an optical phenomenon known as the Airy disk that suggests an incorrect apparent size of stars when looking through such old telescopes. It wasn't until the 1800s that this phenomenon was understood. [0] http://tofspot.blogspot.com/2013/08/the-great-ptolemaic-smackdown.html http://tofspot.blogspot.com/2013/08/the-great-ptolemaic-smac... (part 1)

acqq 8y ago
And still, the whole "The Great Ptolemaic Smackdown" is based on false arguments: The author claims: "the reaction at the time was "WTF? Which heresy are you talking about here?" But the exact heresy was explicitly and very clearly stated both in the sentence by the Inquisition: http://hti.osu.edu/sites/hti.osu.edu/files/documents_in_the_case_of_galileo.pdf http://hti.osu.edu/sites/hti.osu.edu/files/documents_in_the_... "the above-mentioned Galileo, because of the things deduced in the trial and confessed by you as above, have rendered yourself according to this Holy Office vehemently suspected of heresy, namely of having held and believed a doctrine which is false and contrary to the divine and Holy Scripture: that the sun is the center of the world and does not move from east to west, and the earth moves and is not the center of the world, and that one may hold and defend as probable an opinion after it has been declared and defined contrary to Holy Scripture." And in Galileo's Abjuration: http://www.creatinghistory.com/galileo-galileis-abjuration-22-june-1633/ http://www.creatinghistory.com/galileo-galileis-abjuration-2... "after having been judicially instructed with injunction by the Holy Office to abandon completely the false opinion that the sun is the center of the world and does not move and the earth is not the center of the world and moves, and not to hold defend, or teach this false doctrine in any way whatever, orally or in writing; and after having been notified that this doctrine is contrary to Holy Scripture; I wrote and published a book in which I treat of this already condemned doctrine and adduce very effective reasons in its favor, without refuting them in any way" The premise of the whole series by that author is also wrong, approximately, that because the parallax wasn't observed until around 1750 Galileo couldn't prove in 1633 that the Earth is not standing still, therefore the Church was right and it wasn't a matter of faith but a personal thing. It's obviously a completely invalid argument.

Florin_Andrei 8y ago

The epicycle theory was pretty clever and complex, and fully supported by data at the time.

8bitsrule 8y ago
fully supported by data at the time. Not so much; people who -could see- the phases of Venus were in possession of -conclusive- data that it was not moving in a circle between the Earth and Sun. "Although the extreme crescent phase of Venus has been observed with the naked eyes, there are no indisputable historical pre-telescopic records of it being observed." https://en.wikipedia.org/wiki/Phases_of_Venus https://en.wikipedia.org/wiki/Phases_of_Venus There may be no records, but that might not have stopped ANYone with keen eyesight from knowing (including the Greeks back to Aristarchus, or even the Babylonians). For 2000 years, the 'authorities' (e.g. Aristotle) were wrong.
- Florin_Andrei 8y ago
  No, I don't think that would have been considered solid data in any time period. It's almost the definition of "things only very few people claim to see". There are no records of it from the ancient world, and "Venus with horns" could mean anything. > For 2000 years, the 'authorities' (e.g. Aristotle) were wrong. Careful to not let desires and personal aspirations cloud your judgment there.

gmiller123456 8y ago

The author of that article (Graney) on Galileo's observations teaches at a nearby university, and I was able to attend a lecture he gave about the effect. The tl;dr is that when you look through a telescope today stars are pinpoints. You can magnify them as much as you want, and they still appear pinpoints. Brighter stars might appear larger than smaller ones, but their size doesn't change with magnification. Galileo's telescope had such a small aperture that diffraction distorted the image, and the size of the disk of a star did change with magnification. Since they didn't understand diffraction at the time, they thought they were seeing the star's disk. Since there was no measurable parallax on stars at the time, they knew they had to be very far away, and thus unbelievable enormous in order to have a disk visible in a telescope.