Transcript Chapter 16

Toward A New Heaven And A New Earth
Free Response Question 2009
Analyze how Galileo, Descartes, and Newton altered
traditional interpretations of nature and challenged
traditional sources of knowledge.
Traditional Interpretations
and
Traditional Sources of Knowledge
Information credited to Stuart J. Robbins
http://burro.cwru.edu/stu/advanced/pre20th_europe_galileo.html
Cosmological views of the Later Middle
Ages:
Ancient Greeks :
• Aristotle
• Ptolemy
Aristotle
The spherical Earth is
at the center of the
universe, and all other
heavenly bodies are
attached to 56
concentric spheres
which rotate around
the Earth.
Ptolemaic
or
Geocentric
The Ptolemaic order of
spheres from Earth
outward is:
Moon
Mercury
The Earth was in the center of the
universe, from the simple
Venus
observation that half the stars were
Sun
above the horizon and half were
Mars
below the horizon at any time and
Jupiter
the assumption that the stars were
Saturn
all at some modest distance from
Fixed Stars
the center of the universe
Sphere of Prime Mover
The Church’s View
• God created the universe
• God’s greatest creation was earth. “God created
mankind in his own image………”
• Wouldn’t God want his greatest creation to take
center stage in the universe?
The “Common Sense View”
• If the Earth were moving, then wouldn't we feel it,
or feel a strong wind in the direction of
movement?
• Also, if the Earth really moved around the sun,
then wouldn't we see the stars move?
The Human Issue
• The geocentric model puts humans in a special
place at the center of everything.
• It is human nature to want to feel special
• Therefore, your religion offers as one of its
fundamental beliefs that you are not only a
special person, created personally by your divine
being, but you live in a special place: At the center
of everything.
Enter Copernicus:
The Polish astronomer
Nicholas Copernicus
(1473-1543) never liked the
Earth-based view of the
universe……
…….yet he did not publicly announce his views
until he was old. This was due to the Church -anyone who opposed Church doctrine was
branded a heretic, and that would destroy your
reputation, put you in prison, sentence you to
death, or all of the above.
• Copernicus
did not invent the idea of a heliocentric sun-centered - system, but he was the first modern
person to advance it.
• Copernicus' publication On the Revolution of the
Celestial Spheres was not published until after he died in
order for him to avoid being persecuted by the Church.
• The book was published in Latin, so the general public
was not able to read it, therefore there was not much
ado regarding the publication.
• It wasn't even until 73 years after it was published,
1616, that the Church consider it important enough to
place on its Index of Prohibited Books.
• Few learned people were willing to face the Church and
risk death.
However, it did put heliocentric views out in
the restricted open, and it was useful to people
such as Galileo to help revolutionize
astronomy in Europe.
Tycho Brahe
December 14, 1546
October 24, 1601
Tycho Brahe
Before the invention of the telescope, Tycho Brahe
observed the positions of the planets, sun, and nearly 800
stars to an unprecedented accuracy.
The first event was the solar eclipse of 1560. Tycho was
amazed that astronomers were able to predict such
events in advance.
The second was a conjunction of Jupiter and Saturn. It
was the latter event that convinced Tycho that he should
devote his life to studying the sky, for the published
tables that predicted the event were grossly inaccurate,
missing the actual conjunction by several days.
Finally, he saw the supernova. He later wrote in his
book On the New Star", "I noticed that a new and
unusual star, surpassing all the other stars in brilliancy,
was shining almost directly above my head. And since I
had almost from boyhood known all the stars of the
heavens perfectly ... it was quite evident to me that
there had never before been any star at that place in
the sky, even the smallest, to say nothing of a star so
conspicuously bright as this."
Church dogma of the times forbade any changes to the
perfect celestial sphere, so anything that was new must
be atmospheric phenomena.
He firmly stated, "I conclude that this star has never
previously been seen before our time, in any age since
the beginning of the world."
Tycho's heresy moved him to the position of the leading
astronomer of the times. The Danish King, Frederick II,
also took notice of Tycho's fame, and wished to keep him
close to home to glorify the country. In 1576, Frederick II
offered Tycho his own island and funding in the channel
between present-day Denmark and Sweden, where
Tycho could pursue his mapping goals.
Tycho and his assistants transformed the 5 km (3 mile)
long island, Ven, into Europe's center of astronomy.
His observations were the best anyone had ever
been able to make before.
• He increased the accuracy of position
measurements to over seven times more precise
than they had been
• Some of his most accurate observations were 30
times more accurate than those of previous
astronomers.
• Besides accuracy, though, Tycho was interested
in the shear number of observations.
• While previous astronomers were content with
observations a few times in a planet's orbit, Tycho
kept almost continuous records of positions.
• It was through this that many orbital anomalies
that had never been detected were found.
With the death of Frederick II and the rise of Christian IV,
Tycho lost his good standing in Denmark.
In 1599, Tycho left Denmark and came under the grateful
wing of Emperor Rudolf II of Prague.
It was in Prague that Tycho developed a new model for
the solar system. He did not completely believe the
geocentric model, but he didn't completely disbelieve it,
either. He proposed a system that kept the Earth at the
center, but the other planets revolved around the sun in
circles, which in turn orbited Earth in a circle. It was the
"common sense" stability he felt in Earth and the
absence of something observable prevented him from
making the leap to a completely heliocentric model.
Johannes Kepler
Assistant to Tycho
Kepler was given records of the
planetary positions. Hundreds of
pages of data took a very long
time for Kepler to sort through.
Yet Kepler's knack for
mathematics - something his
mentor did not posses - allowed
Kepler to develop his three laws
of planetary motion - laws that
are still in wide use today.
1. Every planet follows an
elliptical orbit around
the sun.
2. An imaginary line from
the center of the sun to
the center of a planet
sweeps out the same
area in the same given
time.
3. The square of a
planet's period (year) is
proportional to the
cube of its distance
from the sun
• Kepler was a very religious man, who found a way to credit
God for each and every discovery he would make, not to
mention his own life and career paths.
• Kepler had originally planned on becoming a priest, but
was drawn into the world of science.
• Furthermore, he was of the Lutheran faith, which caused
him many problems throughout his life, since Germany was
part of the Holy Roman Empire until its dissolution 1806.
• Always being subjected to persecution by the Catholics,
Kepler had to relocate several times due to pressure from
the Church, yet he would not convert.
• Also, mathematicians were not in great demand at the
time, and Kepler did not have very much money to support
his family.
• He lived in poverty, and died in poverty.
The most famous of all
Renaissance scientists, and he is
often considered the founder of
modern astronomy.
Galileo heard of the refracting
telescope, which was invented in
Holland in the very early 1600s,
and built a home-made model in
1609.
Galileo Galilei
With it, Galileo was able to see the four major moons of
Jupiter
Galileo drew detailed diagrams of Earth's moon,
observing valleys and mountains and craters.
He also looked at the sun and
observed dark blemishes on its
surface, which are now called
sunspots.
From the movement of these, he
was able to determine that the
sun has a rotation period of about
one month.
These observations of celestial bodies, published in a
book called The Starry Messenger in 1610
Galileo now has the attention of the Catholic Church
Besides the geocentric model of the universe, the Church
held that celestial bodies, such as the sun and moon,
were prefect - this is a view that probably has its
foundation in the classical texts of the ancient Greeks.
Galileo's observations of spots on the sun and varied
terrain on the moon were in direct opposition to this
doctrine.
Besides these imperfections that he noted in the
celestial globes, Galileo viewed the Jupiter system with
its moons as a small model of our solar system, and he
became convinced of the Copernican heliocentric
model. Making his argument public, Galileo was ordered
by the Church in 1616 to retract his claims that the Earth
rotated around the sun.
• However, Galileo did not, and in 1632 published the
book Dialogue Concerning the Two Chief World Systems.
• In it, he presented two characters, one that argued for
the Copernican model and the other who was a
proponent of geocentricity.
• Time and again in the book, the Copernican believer is
shown to be well-founded in logic and observation.
• Not only did the book present again this forbidden view,
but it was also published in Italian which made it widely
available to the general public.
• Galileo was again brought before the Church, and he
was ordered to retract his claims upon threat of
torture.
• He was then placed under house arrest in 1633
through the end of his life, nine years later on January
8, 1642.
• His book, however, was brought to a press in Holland
where it was published and referred to as Two New
Sciences.
• In 1992, the Catholic Church reconsidered the
Inquisition's findings, and removed Galileo from any
wrongdoings.
Removing body parts from
the corpse was an echo of a
practice common with
saints, whose digits,
tongues and organs were
revered by Catholics as
relics with sacred powers.
There is an irony in Galileo's
having been subjected to
the same treatment, since
he was persecuted by the
Catholic Church for
advocating the theory that
the earth circles the sun,
rather than the other way
around. The Inquisition
forced him to recant and
jailed him in 1634.
Sir Isaac Newton
• The founder of calculus
• Combined Kepler and Galileo on motion
• Mathematical Principles of Natural Philosophy (1687)
known as Principia
- showed how his principle of universal gravitation
provided an explanation both of falling bodies on the
earth and of the motions of planets, comets, and other
bodies in the heavens.
• Humans no longer center of the universe
• Universal Laws of Gravity
• Three Laws of Motion
1. Every object has uniform motion unless acted upon
by a force.
2. The force on an object is equal to the object's mass
times the resulting acceleration
3. For every action, there is an equal and opposite
reaction.
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World Machine – operates in time and space
Connected to founding of Deism
Promoted scientific experiment
Density of earth is five times greater than matter
Rejected Descartes' theory that world is made totally
of matter.