Clay tablet

History of astronomy BC

By qc16.ncampbell
  • 100

    Julian Callender created

    Julian Callender created
    • Julian callender created in 46 BC
    • a regular year of 365 days divided into 12 months with a leap day added to febuary every four months
  • Period: 100 to

    History of astronomy (B.C.)

  • Period: 100 to 200

    The Golden Age

    200BC--1300AD
  • Period: 200 to

    Ancient Era

  • 300

    Gan De

    Gan De
    -Chinease astronomer around 300 BC
    -first known by name to compile a star catolauge
    -made some of the first detailed observations of Jupiter
    -reported a "small redish star" next to jupiter which is believed to be its moon Ganymede
    -divided celestrial sphere into 365.25 degrees, because this was the ammount of days in a tropical year
  • 340

    Callippus determines the leingth of the seasons

    Callippus determines the leingth of the seasons
    Greek astronomer Callippus determines the liength of the seasons (starting at the spring equinox) to be 94 days, 92 days, 89 days, and 90 days
  • 365

    observation of Jupiters moon

    observation of Jupiters moon
    • Chinese astronomer Gan De reported a "small reddish star" next to Jupiter -believed to be Ganymede
  • Jan 1, 1200

    earlyest known star catolauges

    earlyest known star catolauges
    First Babylonian star catalogues dating from about 1200 BC, earlyest we know of
  • Jan 1, 1570

    phenomena of a planet are recognized as periodic

    phenomena of a planet are recognized as periodic
    the tablet of Ammi-saduqa, which lists the first and last visible risings of Venus over a period of about 21 years and is the earliest evidence that the phenomena of a planet are recognized as periodic

  • Mathematics used to determine length of day

    Mathematics used to determine length of day
    -Babylonian tablets document the application of mathematics to the variation in the length of daylight over a solar year

  • Hipparchus

    Hipparchus
    • 190-120 BC -Created Triginometry -created very acurate star catolauge
    • tried to develop heliocentricmodel,but he abandoned his work because the calculations showed the orbits were not perfectly circular as believed to be by the science of the time.

  • Earlyest recorded solar eclipse

    Earlyest recorded solar eclipse
    Earlyest solar eclipse recorded by China in one of the five classics of chinese history

  • Stonehenge is started

    Stonehenge is started
    • the first phase of stonehenge begins, it is believed to be used as a solar/lunar observatory

  • sexagesimal created by Sumerians

    sexagesimal created by Sumerians
    • a sexagesimal is a base 60 place-value number system
      • simplified the task of recording very large and very small numbers -developed around 3000 BC

  • 365 day period of the Egyptian calender in use

    365 day period of the Egyptian calender in use
    the 365 day period of the Egyptian calendar in use
    -observation of stars was important in determining the annual flooding of the Nile