Sistem_Tychonik
Motivasi untuk sistem Tychonik
Berdasarkan fisika, Tycho berpedoman bahwa Bumi terlalu lambat dan berat untuk terus menerus bergerak. Menurut fisika Aristoteles zaman itu, langit (yang terus menerus bergerak dan berputar) terbuat dari bahan "Aether" atau "Quintessence"; bahan ini, tidak dapat ditemukan di Bumi, bersifat ringan, kuat dan tidak berubah, dan keadaan alamiahny adalah gerakan berputar. Sebaliknya, Bumi (dimana benda-benda hanya bergerak jika digerakkan) dan zat-zat penyusunnya bersifat berat dan keadaan alamiahnya adalah istirahat - jadi Bumi adalah benda "malas" yang tidak siap bergerak. Jadi meskipun Tycho mengakui bahwa terbit dan terbenamnya matahari maupun bintang-bintang sehari-hari dapat dijelaskan dengan rotasi Bumi, sebagaimana dikatakan oleh Copernicus, tetapi "gerakan secepat itu tidak dapat dilakukan oleh Bumi, suatu benda yang berat, padat dan such a fast motion could not belong to the earth, a body very heavy and dense and tak tembus cahaya, melainkan dari langit yang bentuk serta bahan konstannya cocok untuk bergerak terus menerus betapapun cepatnya." <!-- In regards to the stars, Tycho also believed that if the Earth orbited the Sun annually there should be an observable stellar parallax over any period of six months, during which the angular orientation of a given star would change thanks to Earth's changing position (this parallax does exist, but is so small it was not detected until 1838, when Friedrich Bessel discovered a parallax of 0.314 arcseconds of the star 61 Cygni ). The Copernican explanation for this lack of parallax was that the stars were such a great distance from Earth that Earth's orbit was almost insignificant by comparison. However, Tycho noted that this explanation introduced another problem: Stars as seen by the naked eye appear small, but of some size, with more prominent stars such as Vega appearing larger than lesser stars such as Polaris, which in turn appear larger than many others. Tycho had determined that a typical star measured approximately a minute of arc in size, with more prominent ones being two or three times as large. In writing to Christoph Rothmann, a Copernican astronomer, Tycho used basic geometry to show that, assuming a small parallax that just escaped detection, the distance to the stars in the Copernican system would have to be 700 times greater than the distance from the sun to Saturn. Moreover, the only way the stars could be so distant and still appear the sizes they do in the sky would be if even average stars were gigantic — at least as big as the orbit of the Earth, and of course vastly larger than the sun. And, Tycho said, the more prominent stars would have to be even larger still. And what if the parallax was even smaller than anyone thought, so the stars were yet more distant? Then they would all have to be even larger still. Tycho said"Deduce these things geometrically if you like, and you will see how many absurdities (not to mention others) accompany this assumption [of the motion of the earth] by inference." Copernicans offered a religious response to Tycho's geometry: titanic, distant stars might seem unreasonable, but they were not, for the Creator could make his creations that large if He wanted. In fact, Rothmann responded to this argument of Tycho's by saying "[W]hat is so absurd about [an average star] having size equal to the whole [orbit of the Earth]? What of this is contrary to divine will, or is impossible by divine Nature, or is inadmissible by infinite Nature? These things must be entirely demonstrated by you, if you will wish to infer from here anything of the absurd. These things that vulgar sorts see as absurd at first glance are not easily charged with absurdity, for in fact divine Sapience and Majesty is far greater than they understand. Grant the vastness of the Universe and the sizes of the stars to be as great as you like — these will still bear no proportion to the infinite Creator. It reckons that the greater the king, so much greater and larger the palace befitting his majesty. So how great a palace do you reckon is fitting to GOD?"