From Geocentric To Heliocentric
In contrast to this, the Earth is imperfect and constantly changing. Aristotle thought that comets must exist inside of the Earth’s sphere, as it was obvious that they didn’t move in perfect circles. The assimilation of Hipparchan observations can no longer be discussed under the aspect of plagiarism.
Ptolemy does this rather cleverly by replacing the abstract geometrical theories by mechanical ones. It may seem strange to the modern reader that someone who wrote such excellent scientific books should write on astrology. Bradley knew that if he could measure the angle that the stars appeared to move, then he could determine how far away they are using trigonometry. Tycho had failed to observe this movement, and Bradley’s observations were not able to provide evidence of parallax either, but he did observe stellar aberration.
People that are moving at a constant velocity are said to be in an inertial frame of … Read More
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