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Why did Ptolemy believe in the geocentric theory?
He believed that the Earth was the center of the Universe. The word for earth in Greek is geo, so we call this idea a “geocentric” theory. In order to make his predictions true, he worked out that the planets must move in epicycles, smaller circles, and the Earth itself moved along an equant.
How did Ptolemy come up with his theory?
Ptolemy accepted Aristotle’s idea that the Sun and the planets revolve around a spherical Earth, a geocentric view. Ptolemy developed this idea through observation and in mathematical detail. In doing so, he rejected the hypothesis of Aristarchus of Samos, who came to Alexandria about 350 years before Ptolemy was born.
How did the geocentric model developed?
In the 6th century BC, Anaximander proposed a cosmology with Earth shaped like a section of a pillar (a cylinder), held aloft at the center of everything. The Sun, Moon, and planets were holes in invisible wheels surrounding Earth; through the holes, humans could see concealed fire.
How did Ptolemy attempt to salvage the geocentric theory?
Ptolemy attempted to salvage the geocentric model by adding ellipticals to each of the planets that revolved around an imaginary point while orbiting around the earth. By doing this, Ptolemy kept the orbits in perfect circles and accounted for the retrograde ( when the planets appear to move backward).
How did Ptolemy’s equant model of the universe work?
Ptolemy’s equant modelIn Ptolemy’s geocentric model of the universe, the Sun, the Moon, and each planet orbit a stationary Earth. For the Greeks, heavenly bodies must move in the most perfect possible fashion—hence, in perfect circles.
Why was copernicus’geocentric model more accurate than Ptolemy’s?
Because the heliocentric model devised by Copernicus was no more accurate than Ptolemy’s system, new observations were needed to persuade those who still adhered to the geocentric model. However, Kepler’s laws based on Brahe’s data became a problem which geocentrists could not easily overcome.
How did scientists come up with the geocentric model of the universe?
Scientists of the 1500s and 1600s inherited a model of the universe whose basic features had been defined by Aristotle 2,000 years earlier. The idea was simple. Earth was stationary at the center and the Sun, Moon, and other planets all moved around Earth. Each object was fixed to a spinning crystalline sphere.