Textbook Notes (368,826)
Canada (162,194)
Astronomy (53)
AS101 (52)
Chapter 3

Astronomy Chapter 3.docx

4 Pages
Unlock Document

Arthur Read

The Origin of Modern Astronomy A Brief History of Ancient Astronomy: • Around 2500 the Egyptians used rising of the star Sirius to mark the beginning of the 365 day calendar o Sirius is brightest stat in the sky • Egyptians were the first to divide the night and day into 12 hours • Hedu’Anna was the first female astronomer named in history • 1400 BCE the Chinese witnessed a brightening and dimming of a “guest star” this is the earliest record of a supernova, although the Chinese did not know it at the time o Chinese also recorded solar and lunar eclipses continuously from the fifth century BCE The Geocentric Model of the Universe: • Aristotle was known as “The Philosopher” throughout the middle ages Nicolaus Copernicus: • Born in 1473 in Poland • Geocentric universe—a model of the universe with Earth at the centre, such as the Ptolemaic universe Copernicus’s Model: • Heliocentric universe—a model of the universe with the sun at the centre, such as the Copernican universe • Copernicus was associated with the roman catholic church all his life and for this reason was afraid to publish his revolutionary ideas that changed the Ptolemaic model and the geomatrey of heaven and hell o What revolutionary ideas?  Believed the sun and not the earth was the centre of the universe  Earth rotated onits axis and revolved around the sun  Began doubting Ptolemy’s model during his college days De Revolutionibus: • Finally published his book in 1542, 12 years after completion • Most important idea in the book was that the sun was the centre of the universe • Earth moves faster along its orbit than the planets that lie farther from the sun • Failed to immediately disprove the geiocentric model for one critical reason—the Copernican model could not predict the positons of the planets any more accurately than the Ptolemaic model could • Planets do circle the sun, not the earth • Most important consequence of the Copernican hypothesis was not what it said about the Sun but what it said about Earth o By placing sun at the centre, Copernicus made Earth move along an orbit like other planets, by making earth a planet Copernicus revoltionized humanity’s view of its place in the universe and triggered a controversy that would eventually bring the astronomer Galileo Lalilei before the Inquisition Tycho Brahe, Johannes, Kepler, and Planetary Motion: • How exactly do the planets move? Tycho Brahe: • Danish • False noses • Replaced by Kepler as Imperial Mathematician Johannes Kepler: • Opposite of Tycho • Oldest of 6 children born in Germany • Became a believer in the Copernican hypothesis • Discovered orbit on mars is an Ellipse, not a circle o A closed curve around two points, called the foci, such that the total distance from one focus to the curve and back to the other focus remains constant • Abandoned ancient belief of ci
More Less

Related notes for AS101

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.