History of Astronomy Ancients - Antiquity

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History of AstronomyAncients - Antiquity

• Amy Nelson
• PHY3901
• September 13, 2004

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Chinese Astronomy

• Mankinds first astronomical records 3000BC
• First recorded solar eclipse -2136BC
• Ahead of their time designs for astronomical
  instruments
• Forecasting solar eclipses
• Devised calendar
• 12 lunar months
• 365.25 days

The Ecliptic Armillary Sphere Qing Dynasty
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Egyptian Astronomy

• In order to maintain power, pharaohs and priests
  used astronomy to predict the annual flooding of
  the Nile
• This yearly flooding was imperative to survival
  in the dry African desert
• Early astronomers discovered the flooding
  coincided with the rise of Sirius
• 25 days after the summer solstice

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Egyptian Astronomy

• 2000BC Amenhotep wrote a catalog of stars
• 5 constellations recorded along with 36 decans.
• Decans were a method of telling time at night
• Each decan rises 40 minutes later every night
• 18 of these decans are used for telling time at
  night
• Only 12 are visible due to dusk and dawn lights

• Egyptians believed that many of the stars and
  planets were actually the gods and goddesses they
  worshipped
• Ra- the sun god traveled in his chariot across
  the sky each day
• Nut- the sky goddess was the actual sky and all
  the stars were her children.
• Pyramids were aligned precisely with Ursa Major
  and Orion.
• These were believed to be the most holy of stars
• In order for the deceased to be reincarnated,
  they had to reach this destination from their
  place of burial.
• Elaborate ceremonies were held called Pedj Shes
  or the stretching of the cord before each
  pyramid was built

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Egyptian Astronomy
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Babylonian Astronomy

• One of the first cultures to base astronomy on
  mathematical theory
• Development of astronomy as a science due to
  inconsistency of lunar months with solar years
• New calendar evenly distributed the months so
  there were not days left over at the end of the
  year
• Earliest records date back to 1800BC
• Had names for several constellations
• Many of todays constellations are simply Greek
  and Latin translations of the Babylonian names

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Babylonian Astronomy

• Eclipses recorded onto a tablet circa 518 and 465
  BC
• Mentions the death of King Xerxes

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Greek and Roman Astronomy

• Became a science
• Based on geometry and mathematics, not physics
• Many new theories emerged from some rather famous
  names

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Greek and Roman Astronomy

• Pythagoras
• 500BC
• Recognized the earth was spherical
• Found that the moon was inclined to the Equator
• Discovered Venus is both the morning and the
  evening star
• Most famous for his theorem
• c² a²b²
• This theorem became an integral tool for the
  measurement of stars

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Greek and Roman Astronomy

• Euxodus
• 370BC
• Developed mechanical system to explain the motion
  of the planets
• Aristotle
• 300BC
• Geocentric theory

• Hipparchus
• 140BC
• Divided stars into groups of apparent brightness
• This system of magnitude of brightness is still
  used today

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Greek and Roman Astronomy

• Ptolemy
• 127-41AD
• Epicycles
• Small circular motion in a larger circular
  motion, or deferent
• Explained retrograde
• Almagest
• Source of all Greek and Roman advances of the
  time
• Geocentric believer
• Ptolemaic theory stood for 1500 years, the
  Renaissance (youll have to wait till next time
  for the exciting heliocentric theory!)

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Greek and Roman Astronomy
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Greek and Roman Astronomy

• Aries- Roman god of War

• Andromeda- daughter of Cepheus and Cassiopeia.
  Taken by Poseidon. Mother of Perseus

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Greek and Roman Astronomy

• Cassiopeia- Queen of Ethiopia who claimed she was
  as beautiful as the Nereids

• Draco- first lawgiver in ancient Greece

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Greek and Roman Astronomy

• Orion- Greek Hunter

• Pegasus- winged horse of Poseidon

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Bibliography

• www.learnwhatsup.com
• www.egyptology.com/astronomy.htm
• www.spacetoday.org
• www.astronomy.com
• www.greek-astronomy.com
• Clagett, Marshall. Ancient Egyptian Science
  Volume II. American Philosophical Society,
  Philadelphia. 1995.
• Hoskin, Michael. The Cambridge Illustrated
  History of Astronomy. Cambridge University Press,
  Cambridge. 1997.
• Lockyer, J. Norman. The Dawn of Astronomy. The
  MIT Press, Cambridge. 1964.
• ONeil, W.M. Early Astronomy From Babylonia to
  Copernicus. Sydney University Press, Sydney. 1986.