Astronomy By Semira Abdu Nov 28/2016 Charted the stars and named - - PowerPoint PPT Presentation

Geometry in Greek Astronomy

By Semira Abdu Nov 28/2016

• Charted the stars and named the constellations
• They Identified the 12 signs of Zodiac
• They further partitioned each sign into 30 degrees so that the

zodiac circle has 360 degrees

• Their system of angular measure like degree, minutes and

seconds still in use today

• They also tracked the movement of the sun, the moon, and at

least three of the five visible planets, Venus, Mars, and Jupiter.

• Predicted Solar and Lunar eclipse

• Refined astronomy from being an observational science with

an element prediction into a full blown theoretical science.

• They understood the night sky like a map
• To the Greeks the universe was a machine that ran upon

mechanical and mathematical principles , which could be deduced through logic and reasoning

• The first notable Greek Philosopher and Astronomer
• He successfully predicted an eclipse in 585 BCE
• He is also credited with inventing trigonometry
• From scattered records, it seems that he believed that the was

flat.

• Better known for his idea about evolution, he was the first

Greek philosopher to create a cosmological model.

• He believes that the earth was cylindrical in shape

• He postulated that the earth was spherical
• He suggested that the movement of the planets, sun , moon

and stars could be described by whole numbers and mathematical precision.he also discovered that the morning and evening stars are the same things the planet Venus.

• He believed that the sun was a huge mass of blazing metal

and the heavenly bodies were rock torn from the earth and set aflame by rapid rotation.

• he believed the earth was flat
• Heraclieds was the first to suggest the sun is the centre of

the universe. A concept that would not be accepted until Copernicusn early 2000 years later

• there two astronomers were a great influence on one of the

most famous philosopher, Plato

• He believed that the entire cosmos was constructed with

precision and that circles and spheres as the most perfect

• bjects and that they were the key to understanding the

universe.

• He proposed that the stars, sun, and moon were fixed to

concentric crystalline spheres rotating inside one another

• Aristarchus teacher of Archimedes was the first astronomer to

make reasonable estimate of the distance of the sun and the moon for the earth.

• he believed that the earth rotated about its axis
• Dm/Rm=Ds/Rs=2pi/720
• sinθ=Rm/Rs

Exam question Express Rm,Rs, and Ds in terms of θ and Dm

https://www.youtube.com/w atch?v=HEheh1BH34Q

* A Survey of classical and modern geometry, Arthur

Banger,2011

* Ede, A. & Cormack, L.B. (2012). A History of Science in

Society: From the Ancient Greeks to the Scientific Revolution, North York, Ontario, Canada: University of Toronto Press

* Lloyd, G.E.R. (2006). Principles and Practices in Ancient

Greek and Ancient Chinese Science. Aldershot, UK: Ashgate

* Tuplin, C.J. & Rihill, T.E. (2002). Science and Mathematics

in Ancient Greek Culture. Oxford, UK: Oxford University Press