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- There were seven models floating around in the early 1600s:
1. Heraclidean. Geo-heliocentric. Mercury and Venus circle the Sun; everything else circles the Earth.
2. Ptolemaic. Geocentric, stationary Earth.
3. Copernican. Heliocentric, pure circles with lots of epicycles.
4. Gilbertian. Geocentric, rotating Earth. (proposed by William Gilbert in De magnete)
5. Tychonic. Geo-heliocentric. Sun and Moon circle the Earth; everything else circles the Sun.
6. Ursine. Tychonic, with rotating Earth.
7. Keplerian. Heliocentric, with elliptical orbits.
See:
* https://tofspot.blogspot.com/2013/08/the-great-ptolemaic-sma...
* ToC: https://tofspot.blogspot.com/2013/10/the-great-ptolemaic-sma...
* PDF: https://faculty.fiu.edu/~blissl/Flynngs.pdf
By the mid-/late-1600s people leaned toward Kepler, mostly because the math was easiest.
With regards to evidence for the Earth's motion, the first inkling was in 1728 with stellar aberration with in γ-Draconis:
* https://en.wikipedia.org/wiki/Aberration_(astronomy)#Discove...
The first for the rotation of the Earth (around an axis) was in 1791 by Guglielmini:
* https://en.wikipedia.org/wiki/Giovanni_Battista_Guglielmini
We finally got parallax in 1806 by Giuseppi Calandrelli in α-Lyrae.
Stellar parallax was considered since at least Aristotle, as he mentions in his On the Heavens (II.14), and since it is not observed then it is reasonable to conclude that there is no motion (it took several thousand years to develop instruments to actually measure it).
Daniel Whitten's "Matters of Faith and Morals Ex Suppositione" is an interesting read.
- > They correctly understood that heliocentrism predicted a parallax but failed to measure that with the primitive observational equipment they had.
Aristotle in De Caelo (Book II, part 14):
> The earth, then, also, whether it move about the centre or as stationary at it, must necessarily move with two motions. But if this were so, there would have to be passings and turnings of the fixed stars. Yet no such thing is observed. The same stars always rise and set in the same parts of the earth.
* http://classics.mit.edu/Aristotle/heavens.2.ii.html
* https://en.wikipedia.org/wiki/On_the_Heavens
See also:
> In the mathēmatikoi tradition of Pythagoreanism the Earth was removed from the center of the universe. The mathēmatikoi believed that the Earth, along with other celestial bodies, orbited around a central fire. This, they believed, constituted a celestial harmony.[24]
* https://en.wikipedia.org/wiki/Pythagoreanism#The_mathēmatiko...
- > Context: Galileo was the first person to see with his own eyes with his first of the kind self-made telescope the moons that are today known as Galilean moons and recognized them as the satellites of Jupiter in March 1610.
Which was not evidence for heliocentrism.
In the early 1600s there were seven models floating around: Heraclidean (geo-heliocentric), Ptolemaic, Copernican (heliocentric, pure circles with lots of epicycles), Gilbertian, Tychonic, Ursine, Keplerian.
Newton, in his Principia (1687), did not use calculus to present his Universal Graviation: rather it was carefully structured in Aristotelian form, with axioms and deductive logic. Kepler's laws can be deduced from principles. Still no coriollis or parallax.
The first inkling of the Earth's motion comes in 1728 when James Bradley detects stellar aberration in γ-Draconis. In 1791 Giovanni Guglielmini finds a 4 mm Coriolis deflection over a 29 m drop, thus providing empirical evidence of rotation. In 1806 Giuseppi Calandrelli publishes "Ozzervatione e riflessione sulla paralasse annua dall’alfa della Lira," reporting parallax in α-Lyrae. So parallax, the chief evidence for the Earth's motion came 250+ years after Galileo.
Stellar parallax was considered since at least Aristotle, as he mentions in his On the Heavens (II.14), and since it is not observed then it is reasonable to conclude that there is no motion (it took several thousand years to develop instruments to actually measure it).
Galileo's chief problems were (a) he was an egotistical jackass, and (b) he had no evidence for what he was claiming to be true. He was allowed to put forward the Copernican model "suppositionally", i.e., as an hypothesis, and "not absolutely". The latter of which, (b), Galileo admitted in his first deposition (12 April 1633): it was concluded that his book put forward the idea 'absolutely', which is where his conviction comes from.
By the late 1600s most folks had switched over to the Keplerian model: not necessarily because they thought it was what was actually happening in reality, but probably because it made the math easier.
For a good timeline of events, see (recently late) Michael F. Flynn's "The Great Ptolemaic Smackdown":
* https://tofspot.blogspot.com/2013/10/the-great-ptolemaic-sma...
Daniel Whitten's "Matters of Faith and Morals Ex Suppositione" is also an interesting read.
- > The theory that the Earth was the center of the universe dates from at least the time of Ancient Greece and is probably more ancient. There's nothing Christian about it, in fact Christian scholars probably took the idea from Ancient Greeks, whom they revered (particularly the Platonists).
It should be noted that the Ancient Greeks did consider the idea of the Earth moving, but there was no empirical evidence for it. Specifically no parallax as even Aristotle wrote in De Caelo (II.14):
> Again, everything that moves with the circular movement, except the first sphere, is observed to be passed, and to move with more than one motion. The earth, then, also, whether it move about the centre or as stationary at it, must necessarily move with two motions. But if this were so, there would have to be passings and turnings of the fixed stars. Yet no such thing is observed. The same stars always rise and set in the same parts of the earth.
* http://classics.mit.edu/Aristotle/heavens.2.ii.html
* https://en.wikipedia.org/wiki/On_the_Heavens
Bradley noticed stellar aberration in ~1728:
* https://en.wikipedia.org/wiki/James_Bradley
Giuseppi Calandrelli finally directly measures parallax in α-Lyrae in 1806.
- > So now the question is: why did Europe care about telescopes, and China didn't?
Copying another comment I made in this thread (much hand-waving and unsubtly/non-nuance):
----
Literacy, individualism, lack of tribalism/clans, a 'mechanistic'/logical/Aristotelian view of reality (which led to the development of science), a 'general' of separation spiritual and civil powers (Matthew 22:15–22, Mark 12:13–17, Luke 20:20–26).
Max Weber (1864-1920) was one of the first people to ask this question:
* https://en.wikipedia.org/wiki/Max_Weber
For more recent thoughts, see The WEIRDest People in the World by Heinrich:
* https://en.wikipedia.org/wiki/The_WEIRDest_People_in_the_Wor...
And Toby Huff (The Rise of Early Modern Science, Intellectual Curiosity and the Scientific Revolution):
* https://en.wikipedia.org/wiki/Toby_Huff
Intellectual Curiosity makes some interesting observations from the historical record: the telescope was invented in 1608 (where it ended up revolutionizing things), and the Europeans brought the technology to Imperial China and Mughal India. They brought it as 'supplicants' to the court to try to grant greater access to each nation; the Jesuits in China used it to show that their 'superior' knowledge of the universe and reality to help with converting folks to Christianity/Catholicism (e.g., by better predicting eclipses).
Neither country was interesting and continued, through a top-down decree, to simply do things the way they always did them.
The telescope arrived in the the Ottoman Empire by osmosis, and they didn't do much with it either.
Fast forward 100+ years and the scientific/technological advances made through curious minds allowed by a different worldview allowed the Europeans to develop more efficient (product output per energy input) economies and then walk all over the rest of the planet. The Indians and Chinese were arguable equally (if not more) advanced in the 1600s, but by the 1700s and later they were 'primitive' in comparison to the Europeans.
----
* https://news.ycombinator.com/edit?id=30742959
> I think this might add some nuance to what "thinking the Earth was flat" meant
To add nuance to nuance: IIRC, the only way to really "prove" or provide evidence of the Earth's motion around the sun was through parallax of stars. Things came close with Bradley and stellar aberration in ~1728:
* https://en.wikipedia.org/wiki/James_Bradley
Giuseppi Calandrelli finally directly measures parallax in α-Lyrae in 1806. The Earth's motion (rotation) around its axis was demonstrated by Guglielmini:
* https://en.wikipedia.org/wiki/Giovanni_Battista_Guglielmini
And it's not like folks didn't think of the possibility, as even Aristotle wrote in De Caelo (II.14):
> Again, everything that moves with the circular movement, except the first sphere, is observed to be passed, and to move with more than one motion. The earth, then, also, whether it move about the centre or as stationary at it, must necessarily move with two motions. But if this were so, there would have to be passings and turnings of the fixed stars. Yet no such thing is observed. The same stars always rise and set in the same parts of the earth.
- > Yes, the lack of star parallaxes were the main argument offered by Tycho Brahe against a moving earth theory.
Much earlier than Brahe. Aristotle in De Caelo (Book II, part 14):
> The earth, then, also, whether it move about the centre or as stationary at it, must necessarily move with two motions. But if this were so, there would have to be passings and turnings of the fixed stars. Yet no such thing is observed. The same stars always rise and set in the same parts of the earth.
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