2 5 renaissance naissance birth
Download
Skip this Video
Download Presentation
2-5 Renaissance “naissance” = “birth”

Loading in 2 Seconds...

play fullscreen
1 / 79

2-5 Renaissance “naissance” = “birth” - PowerPoint PPT Presentation


  • 87 Views
  • Uploaded on

2-5 Renaissance “naissance” = “birth”. The belief that the cosmos is ultimately understandable slowly emerges again. Revival of art. The Birth of Venus, Botticeli, 1485. Rediscovery of perspective (and geometry). Delphic Sybil, Michelangelo,1510 - 1512. Rediscovery of light.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about '2-5 Renaissance “naissance” = “birth”' - davida


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
2 5 renaissance naissance birth

2-5 Renaissance“naissance” = “birth”

The belief that the cosmos is ultimately understandable slowly emerges again

revival of art
Revival of art

The Birth of Venus, Botticeli, 1485

slide5
Rediscovery of light

Lady with an ermine, Vinci

slide7
More liberal period

The creation of the planets, the Sun and the Moon, Michelangelo

slide8
Rediscovery of sculpture

Middle Age bas-relief

Figures hardly stick out of the stone

slide10
David, Michelangelo

Perfect knowledge of the human body

Greek art

slide11
A time of conquests and adventure

Magellan’s travel around the Earth: 1519

giordano bruno 1548 1600
Giordano Bruno (1548 – 1600)

Early champion of the heliocentric model: “the Sun, not the Earth, is the centre of the universe”

Also believed:

In the existence of inhabited planets

That the universe is infinite

But before all, dreamt of a radical reform of Christianity

slide14
Bruno went to Rome to convince the Pope himself!

?

1600: Bruno was burnt by the Holy Inquisition

Often portrayed by scientists as a martyr of science

nicolas copernicus 1473 1543
Nicolas Copernicus (1473 – 1543)

Priest interested in mathematics and astronomy

Understood that stellar parallax is not observed because stars are too far

Goal: to predict the position of the planets

ptolemy s geocentric model
Ptolemy’s geocentric model

Very complex calculations !

slide18
Mars

Earth

Moon

Jupiter

Saturn

Venus

Mercury

Sun

slide19
A

B

A overtakes B. What does A see of B?

B seems to be moving backward

slide20
A

B

Now B overtakes A. What does A see of B?

B is moving forward

A: “B has moved back and forth”

he could reproduce the retrograde motion of mars in very simple manner
He could reproduce the retrograde motion of Mars in very simple manner

Like in a car race, the Earth is sometimes overtaking Mars, giving us the impression that Mars is moving backward

slide22
Copernicus also deduced that the nearer a planet is to the Sun, the greater its orbital speed

Mercury orbits at a higher speed than Mars

slide24
Jupiter

Earth

Mercury

slide25
Jupiter

Earth

Mercury

slide26
Copernicus was a priest and had no intention to contradict the Scriptures

He did not claim his model described the actual motion of the Earth. It was just a mathematical trick.

slide27
Nevertheless, he chose to publish his De Revolutionibusafter his death

His model: no better accuracy than Ptolemy’s => was not widely accepted until more than a century

slide28
People were not ready to believe that the Earth was moving

They argued that if the Earth were rotating, we would feel its motion

slide30
At that time, logical reasoning had more weight than any observation or experiment

Anyway astronomers had no telescope…

tycho brahe 1546 1601
Tycho Brahe (1546 – 1601)

Born three years after Copernicus’ death

slide33
He made a continuous record of the position of the Sun, Moon and planets for almost 20 years

Found that the predictions of Ptolemy’s model were inaccurate

Tycho measuring the altitude of a celestial object, 1587

slide34
Five planets orbiting around the Sun

He believed in a modified geocentric model

Sun

Earth

Moon

All planets orbit around the Sun but the Earth!

slide35
In 1597, Brahe’s patron the Danish King Frederick II died

Brahe had to find a new job…

He became court astronomer to the Emperor Rudolf of Bohemia, in Prague, Austria

There he met a diligent assistant: Johannes Kepler

kepler 1571 1630
Kepler (1571 - 1630)

Theology student

Became convinced that all the planets are actually orbiting the Sun

slide37
Brahe was reluctant to give full access to data to Kepler, fearing his bright assistant would discover the secret of the universal motion

When Brahe died, Kepler got full access to Brahe’s records, that he studied for more than 20 years

At the age of 38, he finally published his first results

slide39
The orbit of a planet is an ellipse

ecliptic

top view

Sun

planet

how to draw an ellipse
How to draw an ellipse?

Position of the Sun

Focus

Focus

slide41
Eccentricity of an ellipse: e

An ellipse which does not differ much from a circle is not “very eccentric”

e is close to zero

An ellipse which is very elongated has an eccentricity close to 1

slide44
Very similar to a circle

Caution: same orbit seen from two different points of view

Top view

Side view

kepler s second law
Kepler’s second law

A planet:

Speeds up as it comes closer to the Sun

Slows down as it moves away from the Sun

Lowest speed

Highest speed

Sun

kepler s third law
Kepler’s third law

P: orbital period (time needed for one revolution), in years

a

a: semimajor axis, in AU

a3 = P2

slide61
Mercury

Mars

Jupiter

slide62
Mercury

Closer to the Sun

slide64
Mercury

Mars

Jupiter

slide66
Kepler knew the orbital periods of the planets (P)

He could estimate the distance from each planet to the Sun (a), in AU

This was a nice model, but yet it did not explain why the planets were orbiting the Sun

Meanwhile, a genius was at work in Florence, Italy…

answers
Answers

NUMISMATICS

ad