2. Ancient Astronomy

2. Ancient Astronomy - Astronomy of the Ancients Outline...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
3- Astronomy of the Ancients Our goals for this section: To learn about some of the earliest civilizations to practice astronomy: the Mesopotamians, the Egyptians, and the early Greeks To distinguish between ancient and modern astronomy—motives and methods Outline
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3- Ancient astronomy was primarily descriptive and mythological, lacking the element of physical explanation Ancient astronomers were much more concerned with predicting various phenomena (eclipses, planetary motions, etc.) than with reasoning out the explanations for these phenomena e.g. ancient Egyptians believed eclipses occurred when great cosmic sow devoured the Moon—as long as they could predict events, they were often happy to invent causes Ancient astronomy—with few exceptions—was largely astrological Motivations of Early Astronomers Astrology : a pseudoscience based on the belief that the configuration of celestial objects influences peoples’ personalities, chance events, etc.
Background image of page 2
3- The archaeological record shows that, by the time writing was invented, early civilizations already had well- established traditions of studying the night sky The Earliest Astronomers e.g. Newgrange www.newgrange.com
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3- Mesopotamians (among whom the Babylonians were one subgroup) --> first to keep long-term records Many concepts of Mesopotamian astronomy are still in use The Mesopotamians were building massive observatories by about 3800 B.C.
Background image of page 4
3- 1. They were the first to divide a circle into 360 o , a degree into 60 arcminutes, and an arcminute into 60 arcseconds . The ‘o’ symbol used to denote ‘degrees’ was originally a symbol for the Sun. The use of 360 degrees reflects the approximate period of the Sun’s apparent motion around the sky (365.24 days). The Mesopotamians originated several concepts still in use:
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3- 2. The Babylonians grouped stars together into figures called constellations (from Latin, ‘com-’ + ‘stella’ ‘stars together’), many of which are nearly identical to the ones used today. Orion
Background image of page 6
3- 3. The Mesopotamians recognized that the annual apparent motion of the Sun along the ecliptic carried it through 12 constellations, which we now refer to collectively by their Greek name, the zodiac .
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3- The pattern of the Sun’s annual apparent motion was well known to the Mesopotamians, but not its cause .
Background image of page 8
3- The Babylonians developed sophisticated and accurate astronomical and mathematical techniques for predicting the motions of celestial bodies, but never quite developed astronomy as a science The idea of the universe as a system subject to natural laws was first developed in about 600 B.C. by the Greeks Thus, for more than 5000 years, astronomy existed as an essentially predictive discipline, and the various pictures of the universe were probably all purely descriptive – “when, not why” Early Greek Astronomy
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
3- Pythagoras (c582-c500 B.C.) and his followers introduced two key ideas -->foundation for new generations of highly successful and increasingly physical astronomical models --> not just
Background image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/01/2011 for the course ASTRO 1a03 taught by Professor Samantha during the Spring '11 term at McMaster University.

Page1 / 45

2. Ancient Astronomy - Astronomy of the Ancients Outline...

This preview shows document pages 1 - 11. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online