1. Standard memberadam warlock
    Baby Gauss
    Ceres
    Joined
    14 Oct '06
    Moves
    18375
    29 May '14 18:10
    A little introduction on how heliocentricity entered the collective european mind and how it really went down

    The telescopic discoveries, which Galileo was the first to publish, shock up the whole of Europe and not just the Catholic Church. However the contents of Sidereus Nuncius neither disproved Ptolemaeus/Peuerbach nor did they prove Copernicus, as I’ve already explained here. Of course at first they did nothing at all because like all new scientific discoveries they needed to be confirmed by other astronomers. This proved to be somewhat difficult, as the available telescopes were very poor quality and Galileo was an exceptional telescopic observer. In the end it was the Church’s own official astronomers, the members of Clavius’ mathematical research group at the Collegio Romano, who with the active assistance of Galileo delivered the necessary confirmation of all of Galileo’s discoveries.


    http://thonyc.wordpress.com/2014/05/29/galileo-the-church-and-heliocentricity-a-rough-guide/
  2. Standard memberDeepThought
    Losing the Thread
    Cosmopolis
    Joined
    27 Oct '04
    Moves
    78625
    29 May '14 20:08
    Heliocentrism was probably invented by Aristarchus of Samos sometime around 300 BC. He got the then known planets in the right order as well. Cleanthes of Assos wanted him tried for impiety. It took another 1,700 years for the idea to finally be proved right.
  3. Standard memberadam warlock
    Baby Gauss
    Ceres
    Joined
    14 Oct '06
    Moves
    18375
    29 May '14 20:34
    Originally posted by DeepThought
    It took another 1,700 years for the idea to finally be proved right.
    Who proved the idea right?
  4. Joined
    11 Nov '05
    Moves
    43938
    30 May '14 11:58
    What does heliocentricity means? Is this the current theory of everything?

    Geocentricity - that the Earth is the centre of the Universe.
    Heliocentricity - that the sun is the centre of the Universe.
    Galactocentricity - that the Milky Way was the centre of the Universe.
    Neniocentricity - that there is no real centre in the Universe.

    So what is the current theory?
  5. Germany
    Joined
    27 Oct '08
    Moves
    3081
    30 May '14 16:13
    Originally posted by FabianFnas
    What does heliocentricity means? Is this the current theory of everything?

    Geocentricity - that the Earth is the centre of the Universe.
    Heliocentricity - that the sun is the centre of the Universe.
    Galactocentricity - that the Milky Way was the centre of the Universe.
    Neniocentricity - that there is no real centre in the Universe.

    So what is the current theory?
    Heliocentricity usually refers to the idea that the Sun is the center of the Solar system. This choice is actually arbitrary, but is usually made because planetary orbits look "nicer" when you pick the Sun as the center. Also, the center of gravity of the Solar system is close to, but not equal to the center of gravity of the Sun itself.

    According to the current Big Bang theory, the Universe has no center, nor an edge. It is space itself that is expanding in a self-contained way.
  6. Subscribermoonbus
    Uber-Nerd
    Joined
    31 May '12
    Moves
    2047
    31 May '14 07:02
    Originally posted by adam warlock
    Who proved the idea right?
    Copernicus, if I recall correctly, wrote the theoretical side of it, and Galileo provided the empirical proof of it. Others may have reached the same conclusion independently, of course, but those two ultimately got the laurels.
  7. Standard memberadam warlock
    Baby Gauss
    Ceres
    Joined
    14 Oct '06
    Moves
    18375
    31 May '14 09:34
    Originally posted by moonbus
    Copernicus, if I recall correctly, wrote the theoretical side of it, and Galileo provided the empirical proof of it. Others may have reached the same conclusion independently, of course, but those two ultimately got the laurels.
    Why do you consider Copernicus to have prove it theoretically speaking? Why not Aristarcus for instance? What do you make of the fact that Copernicus model of the Solar System had more circles than Ptolomeus' model?

    Galileo certainly hasn't made no such empirical proof of the heliocentic model. He indeed proved that a purely geocentric model of the Solar System was wrong but that doesn't rule out a thyconic model for instance.
  8. Subscribermoonbus
    Uber-Nerd
    Joined
    31 May '12
    Moves
    2047
    31 May '14 11:331 edit
    Originally posted by adam warlock
    Why do you consider Copernicus to have prove it theoretically speaking? Why not Aristarcus for instance? What do you make of the fact that Copernicus model of the Solar System had more circles than Ptolomeus' model?

    Galileo certainly hasn't made no such empirical proof of the heliocentic model. He indeed proved that a purely geocentric model of the Solar System was wrong but that doesn't rule out a thyconic model for instance.
    While it is documented that Aristarchus proposed heliocentrism, he had not the technical means to back up the claim with observational data. It was an astonishingly prescient philosophical speculation, but hardly constitutive of a proof.

    Copernicus published a book, 'on revolutions...' which truly revolutionized science in the middle ages and gave the heliocentric theory the necessary mathematical basis to stand up to empirical testing (I.e., the ability to calculate where planets should be observed at any point in time). Galileo made significant improvements to observational techniques, enabling empirical confirmation of Copernicus' theory. It is clear from statements made to the Inquisition and other accounts from the time that galileo thought of himself as confirming Copernicus' work, whatever other theories there may have been.

    http://en.wikipedia.org/wiki/Galileo_Galilei
    http://en.wikipedia.org/wiki/Nicolaus_Copernicus

    Extensive references are listed at the ends of both articles.
  9. Subscribermoonbus
    Uber-Nerd
    Joined
    31 May '12
    Moves
    2047
    31 May '14 13:52
    There appears to be some misconception what Copernicus proved. I shall attempt disambiguation. Astronomers had for thousands of years kept records of the positions of planets, with ever-increasing accuracy. These data were published in almanacs. Mathematicians had used these observational data to advance theories of celestial motion consistent with the observed data. Viewed from earth, some planets appear to move past us and then reverse course briefly, to be passed by us, and speed up again and overtake us. This is called retrogression. In order to account for this, the Ptolemaic or geocentric theory must assume that planets do not describe circular or elliptical orbits, but rather flattened corkscrews around us. Before Copernicus, the mathematics had been worked out to accurately predict the positions of the known planets according to these spirals within spirals. Because the geocentric position had been assumed to be correct, no one had tried to work out the equations based on a heliocentric position. So, before Copernicus, one of the standard refutations of heliocentricity was that the geocentric theory had already been 'proven' mathematically--that is, the positions could be accurately predicted. What Copernicus did was to work out the equations for the heliocentric theory, thereby showing that two possible mathematical systems were consistent with the observed data.

    It remained to provide empirical observations to demonstrate which of the two systems was factually correct. This depended on telescopic observations, and Galileo contributed significantly to this part of the 'proof'.
  10. Standard memberadam warlock
    Baby Gauss
    Ceres
    Joined
    14 Oct '06
    Moves
    18375
    01 Jun '14 05:15
    Originally posted by moonbus
    There appears to be some misconception what Copernicus proved. I shall attempt disambiguation. Astronomers had for thousands of years kept records of the positions of planets, with ever-increasing accuracy. These data were published in almanacs. Mathematicians had used these observational data to advance theories of celestial motion consistent with the obser ...[text shortened]... d on telescopic observations, and Galileo contributed significantly to this part of the 'proof'.
    What Copernicus did was to work out the equations for the heliocentric theory, thereby showing that two possible mathematical systems were consistent with the observed data.

    Yes you're right about this. Let me just add that Copernicus heliocentric system was actually worse than Ptolomeus system in predicting planet position as it stands on its own book.

    While it is documented that Aristarchus proposed heliocentrism, he had not the technical means to back up the claim with observational data.

    What Aristarchus lacked was not the observational data but a complete mathematical model as you so well said in your following post.

    It is clear from statements made to the Inquisition and other accounts from the time that galileo thought of himself as confirming Copernicus' work

    Yes, its pretty clear that Galileo really thought that.

    It remained to provide empirical observations to demonstrate which of the two systems was factually correct. This depended on telescopic observations, and Galileo contributed significantly to this part of the 'proof'.

    No he didn't. Because no telescope of Galileo's time could produce a proof a heliocentric solar system. What Galileo and others did was disprove a total geocentric solar system and that's that.
Back to Top