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Mesopotamia
Western astronomy finds its origins in Mesopotamia. Mesopotamia means "land between rivers" and refers to the Tigris and the Euphrates. This is the location of the ancient kingdoms of Sumer, Assyria and Babylon. Cuneiform emerged as a writing system some time around 3500 - 3000 BC.
There are early Babylonian star catalogues that date to about 1200 BC. This is where our knowledge of Sumerian astronomy comes from.
The Babylonians were the first to recognize that astronomical phenomenon were periodic. They also applied mathematics to their predictions. There is also the Enuma Anu Enlil, which is a series of about 70 tablets. These tablets consists in a series of omens and are dealing with Babylonian astrology. Tablet 63 is known as the Venus tablet. This tracks the first and last visible risings of Venus for about 21 years. There is also the MUL.APIN, which deals with various aspects of Babylonian astrology. It also:
contains catalogues of stars and constellations
contains schemes for predicting the heliacal rising and setting of planets
lengths of daylight
India
Astronomy was used to create calendars during the 3rd millennium BCE during the period of the Indus Valley Civilization. The Indus Valley Civilization did not really leave around written documents. The oldest Indian astronomical text that we have comes from the Vedic period (c. 1500 - c. 1100 BCE). This text is known as the Vedanga Jyotisha and its author is traditionally known as "Lagadha." The Vedanga Jyotisha describes rules for tracking the motions of the Sun and the Moon. This was for the purpose of ritual.
Aryabhata
Aryabhata, lived from 476 to 550 and was the first major mathematician-astronomer, who in 499, wrote Aryabhatiya. Aryabhatiya was a Sanskrit astronomical treatise.
Aryabhata assumed that the Earth was spinning on its axis. Periods of the planets were given with respect to the Sun. Many astronomical constants were accurately calculated, such as:
the periods of the planets
times of the solar and lunar eclipses
the instantaneous motion of the Moon
During the Shunga Empire (185 - 75 BCE), many star catalogues were produced. This was known as the golden age of astronomy for India. It saw:
calculations for the motions and places of various planets
their rising and setting
conjunctions
the calculation of eclipses
By the 6th century, Indian astronomy had assumed that comets were celestial objects that re-appeared periodically. Varahamihira and Bhadrabahu express this view in the 6th century and in the 10th century, Bhattotpala, listed names and estimated periods of some comets. Unfortunately, it was not known how accurate Bhattotpala was in his calculations.
Bhaskara II (1114 - 1185), was head of an astronomical observatory in Ujjain. Bhaskara's work was known as Siddhantasiromani and it consisted in 2 parts:
1. Goladhyaya (sphere)
2. Grahaganita (mathematics of the planets)
Bhaskara also calculated the time it would take the Earth to orbit the Sun.
Greece
Astronomy, for the ancient Greeks, was a branch of mathematics. They developed astronomy to a highly developed level.
Eudoxus of Cnidus
Callippus
Herclides Ponticus
Eudoxus of Cnidus and Callippus, in the 4th century BCE, gave the first geometrical, 3-dimensional models to explain the apparent motion of the planets.
Herclides Ponticus proposed that the Earth rotates around its axis.
Plato
Aristotle
The natural philosophers Plato and Aristotle to a different approach to celestial phenomenon. They were searching for the reasons behind the motions of the Cosmos.
Plato, in his Timaeus, describes the Universe as a spherical body. It is divided into circles that carry the planets. It is also governed according to a world soul.
Aristole, followed the mathematics of Eudoxus of Cnidus, proposing that the Universe is composed of a complex series of concentric spheres. Their circular motion keeps the planets around the Earth.
This was the cosmological model that prevailed (in its various forms) until the 16th century.
Aristarchus of Samos
Eratosthenes
Aristarchus of Samos, in the 3rd century BCE, was the first to suggest a Heliocentric system. Only fragments of his ideas still exist today.
Eratosthenes was able to estimate the circumference of the Earth to a remarkable degree of accuracy.
Apollonius of Perga
Hipparchus
Apollonius of Perga, then later, Hipparchus (2nd century BCE), will develop models where and eccentric circle carriers around a smaller circle. This smaller circle was called an epicycle and it carries a planet.
Hipparchus' contributions:
the first measurements of precession
star catalog
proposed our modern system of apparent magnitudes
What also should be noted is the Antikythera mechanism. This was an ancient Greek astronomical observation device. It was especially for calculating the movements of the Sun and the Moon, potentially the planets and dates from about 150 to 100 BCE. This was the first ancestor of an astronomical computer.
It was discovered off of a ship wreck near the Greek island of Antikythera. The device is famous for its use of a differential gear. This was previously believed to have been first used in the 16th century.
Ptolemy
Ptolemy, in 2nd century Greece, writes Almagest, a treatise on the apparent motion of Stars and planetary paths. This work had a lasting effect on astronomy up until the Renaissance.
Ptolemy also ventured into the world of cosmology with his Planetary Hypothesis. He developed a physical model of his geocentric system.
Egypt
Knowledge of the heavens in the 3rd millennium BCE is demonstrated by the Egyptians. They show this knowledge by the precise orientation of the pyramids. Indeed, the pyramids are aligned toward the pole star. Because of the precession of the equinoxes, that pole star was Thuban. Thuban is a faint star in the constellation Draco.
The temple of Amun-Re has also been evaluated. This temple is located at Karnak. This "Great Temple" was aligned to the rising of the midwinter Sun.
Egyptians also found the position of Sirius or the "god star." The Egyptians believed that Sirius was Anubis, moving through the heavens. Anubis is the God of death, the afterlife, and the Underworld. The position of Sirius was critical to their civilization. When it rose heliacal in the east before sunrise, it foretold the flooding of the Nile.
Astronomy played a large part in the daily lives of the Egyptians. For example, in religious matters, astronomy was used for fixing dates of festivals and determining the hours of the night. They also attempted to record phases of the Sun, Moon and Stars.
China
East Asian astronomy begins in China, which has a long history of astronomy. There are detailed records of astronomical observation from the 6th century BCE to the 17th century. The 17th century saw the introduction of Western astronomy and the telescope. Eclipses were able to be accurately predicted by the Chinese.
Most of early Chinese astronomy was for the purpose of keeping time.
There was also astrological divination in China. Astronomers would take note of "guest stars" that would appear among the fixed stars.
The Chinese were the first to report a supernova in 185.
Also, the world's first star catalog was made by Gan De, in the 4th century BCE.
Mesoamerica
There are Maya astronomical codices for calculating:
phases of the Moon
the recurrence of eclipses
the appearance and disappearance of Venus
The Maya based their calendars on the carefully calculated cycles of the Pleiades, the Sun, the Moon, Venus, Jupiter, Saturn and Mars.
6 pages from the Dresden Codex
They also had a precise description of the eclipses. This is as they were depicted in the Dresden Codex, a Mayan book that dates to the 13th or 14th century.
The Milky Way was also crucial to their cosmology.
There are also a number of important Maya structures that appear to be oriented toward the extreme risings and settings of Venus. For the ancient Maya people, Venus was the goddess of war. Thus, many recorded battles are said to be timed to the motion of this planet. Mars is also mentioned in preserved codices and mythology.
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