If the Earth is rotating about its axis, and.The heliocentric model was generally rejected by the ancient philosophers for three main reasons: This model became known as the heliocentric model of the Solar System. Order of the planetary orbits is as follows: Mercury, Venus, Earth, Mars, Jupiter, Saturn-with MercuryĬlosest to the Sun. Moreover, the Moon orbits around the Earth, and the Earth Since a circle is the most ``perfect'' imaginable shape, it follows that heavenly objects must executeĪ second Greek philosopher, Aristarchus of Samos (310-230BC), proposed anĪlternative model in which the Earth and the planets execute uniformĬircular orbits around the Sun-which is fixed. The ancients believed the heavens to be the realm of perfection. For obvious reasons, Eudoxas' model became known as the The order of the orbits is as follows: Moon, Mercury, Venus, Sun, Mars, Jupiter, Saturn-with The Sun, the Moon, and the planets all execute uniform circular orbits around the Earth-which is The first scientific model of the Solar System was outlined by the Greek philosopherĮudoxas of Cnidus (409-356BC). Moreover, Mercury and Venus can sometimes be seen to transit in front of the Sun. Noted that the Moon occasionally passes in front of the Sun andĮach of the planets. It was also recognized that some bodies were closer to the Earth Passes in front of, and blocks the light from, stars in its path. That the wandering bodies were located within this sphere: e.g., because the Moon clearly To a ``celestial sphere'' which formed the outer boundary of the Universe. The ancients believed that the stars were fixed Planets-Mercury, Venus, Mars, Jupiter, and Saturn.
Visible to ancient peoples: the Sun, the Moon, and the five The positions of the planets in the sky could be used to foretell important events.Īctually, there were only seven ``wandering'' heavenly bodies Planets were vital to astrology: i.e., the belief-almost universally prevalent in the ancient world-that Moon were important for determining the calendar, and also for navigation. In ancient times, much of this interest was of a practical nature. The Sun, the Moon, and the objects which the ancient Greeks called plantai (``wanderers''), and which we call Humankind has always been fascinated by the night sky, and, in particular, by the movements of
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