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The early Chinese were accomplished astronomers. In fact, they made the first record of a solar eclipse in 2136 BC. Although the Chinese knew of the five visible planets, much of their early astronomy was focused on the records and predictions of supernovas and comets.

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The early Egyptians also gazed at the night skies and became skilled in astronomy. The names they applied to the planets were those of their gods. Mercury was called Thoth, the great measurer - a divinity associated with knowledge, and the inventor of speech, writing, and arithmetic.

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Early Greek civilization, from 1400 to 200 BC, made many contributions to astronomy. Unlike other early astronomers who were astrologers as well, Greek astronomers were often considered philosophers and mathematicians, as we know from the works of those such as Plato and Eudoxus.

Around 450 B.C. the Greeks started studying the motions of the planets and using geometry to measure the size of the Earth, Sun and Moon. Mercury was known by two different names, associated with its evening and morning appearances. These were Apollo (god of truth, the arts, archery, plagues, and divination) and Hermes (god of writing and messenger to the other gods). Plato and Eudoxus reported that the synodic and sidereal periods of Mercury were 110 days and 1 year respectively. Later Greek astronomers made detailed star charts and determined planetary motions, often building on earlier work. In 200 AD the Greek astronomer Ptolemy completed his Almagest, a comprehensive text of mathematical astronomy. Translated into Latin around 1400 AD, Ptolemy’s work was considered by Europeans to be the authority on astronomical understanding until the early 1600’s. Ptolemy’s model of the solar system was geocentric, or Earth-centered. The Sun and planets were thought to travel around the Earth from east to west, with the planets moving on more complicated cyclic paths about their average positions.

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As did other ancient civilizations, the Hindus interwove astronomy and astrology. They believed that the location of the planets in the sky at the time of birth determined a person’s future. The Hindus called the planets collectively “navagrahs” and references to them can be found on temple markings. As in other early cultures, the planets were given the names of divinities; Mercury was called Budha.

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A Concise History of Science in India, D.M. Bose, S.N. Sen & B.V. Subbarayappa (Indian National Science Academy, New Delhi, 1971).

The Mayas

The Mayas lived in an area of Central America that now includes Guatemala, Belize and El Salvador, as well as parts of Mexico, Honduras and Nicaragua.

Mayan astronomers were primarily interested in the “Zenial Passages” – times when the Sun crossed over certain Mayan latitudes. Mayan astronomy is thought to have developed in the period from 1500 BC to 800 BC. Much of what we know of it is found in writing known as the Dresden Codex, a band of paper 3.5 meters long arranged in 39 sheets. This contains information regarding the calendar system, astronomical data and sky mechanics, as well as tables of multiple integers thought to have been used in the calculations of planetary movements.

The Mayas were also deeply interested in the planet Venus, believing it to be as important as the Sun. But the Mayas charted the motion of the planet Mercury as well; records of their detailed observations are found in the Dresden Codex. These include the appearance of Mercury as a morning star in 733 B.C. and as an evening star in 727. The Mayans also calculated that Mercury would rise and set in the same place in the sky every 2,200 days.

dresden codexDresden Codex 2

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Mesopotamia is a region in present-day Iraq between the Tigris and Euphrates rivers. Translated from its Greek origin, it means “between the rivers”. Some archeologists believe that the world’s earliest cities emerged in this region around 6000 B.C.

Mesopotamia Map

The inhabitants of Mesopotamia from about 3500 B.C. to about 2000 B.C. are referred to as Sumerians. This civilization developed a written language using signs for words and syllables; their writing is preserved on clay tablets. They are thought to have studied the movements of the Sun, the Moon and the visible planets, although no written records of such observations from this early period remain. In this, as in many other early cultures, the motions of celestial objects were of great interest because of their religious significance, and particularly because they were thought to give clues about the future course of human events. We now call this belief astrology and distinguish it from astronomy, the scientific study of the heavens.

Sumerian TabletThe Sumerians named the Sun, the Moon and the visible planets - including Mercury - after their greatest seven gods. Translations from surviving cuneiform tablets reveal that Mercury was designated by many names, including that transcribed by archaeologists as MulUDU.IDIM.GU.UD. Mercury was often associated with Nabu, or Ninurta, the god of water and writing. Later, in Akkadian, it became known as Shikhtu, meaning “jumpy”.

The Sumerian civilization was succeeded by the Babylonians, a culture that inherited writing, astronomy, and mathematics from the Sumerians. Early Babylonian astronomers (2000 – 1000 B.C.) may have recorded their observations of the sky: Although no records from that period have survived, tablets from the 7th century B.C. refer to observations of Venus supposedly made much earlier, during the reign of King Ammisaduqa (1702 – 1682 B.C.). We also know that from 800 B.C. onward the Babylonians cataloged stars, kept records of records of solar eclipses and the time intervals between new moons, and were able to predict some astronomical phenomena.

The Babylonians named Mercury after their divinity Nebo or Nabu, - the record keeper, god of writing, and messenger to the gods. As Mount Sinai in Egypt is named for the Babylonian moon god Sin, Mount Nebo, in present-day Jordan, is named after the Babylonian god of the planet Mercury. In Babylonian astronomy Mercury was associated with both sexes because of its appearance as both an evening and a morning star.

Later Babylonian civilizations (600 B.C. – 200AD) were yet more advanced in mathematics and astronomy. Their catalog of the stars forms the basis of our zodiac. They also made detailed observations of the movements of the five visible planets, including Mercury.

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The Babylonian Theory of the Planets, N. M. Swerdlow. Princeton University Press, 1998.

Northern Europe

To the northern peoples, Mercury was named Odin, the supreme god. Often referred to as the god of wisdom, magic, and war, and the inventor of runes, his name means "inspired one". Odin was worshipped throughout northern Europe (including Britain), wherever the Vikings and other Nordic peoples settled. Odin was also known as Woden, and it is from this form that the English word for Wednesday is derived.

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