Galileos Telescopic Observations

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Galileos Telescopic Observations

• Ted Georgian
• Clare 102
• Spring 2007

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Web sites with useful animations

• Clare 102 Some Useful Web Sites on the
  History of Astronomy T. Georgian, Spring
  2007
• Measuring the Earth and the Solar system
  http//galileo.phys.virginia.edu/classes/109N/lec
  tures/gkastr1.html
• Eudoxus homocentric spheres model of planetary
  motion Select Window Media 9 movie
• http//brunelleschi.imss.fi.it/genscheda.asp?appl
  SIMxslmultimedlinguaENGchiave500052
• Ptolemys and Copernicus explanations of
  retrograde motion http//alpha.lasalle.edu/smit
  hsc/Astronomy/retrograd.html
• Phases of Venus as explained by Ptolemys
  modelhttp//rt210.sl.psu.edu/phys_anim/astro/pto
  lemy_v_phases_avi.html
• Phases of Venus as explained by Copernicus
  model http//rt210.sl.psu.edu/phys_anim/astro/co
  pernicus_v_phases_avi.html

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Retrograde motion done with an epicycle
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Retrograde motion done with differentplanetary
velocities
http//alpha.lasalle.edu/smithsc/Astronomy/retrog
rad.html
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• Ptolemys model
• fit traditional views of the world
• made accurate predictions
• complex and arbitrary
• explained all known evidence

• Copermicus model
• required a radical rethinking of ones view of
  the world
• made less accurate predictions
• simple and only one form would work
• predicted stellar parallax not observed

Late 1500s ?
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Galileo Galilei (1564-1642)

• born in Pisa, in the Tuscany region of Italy
• fathered three children out of wedlock with
  Marina Gamba
• in 1581 began studying at the University of Pisa
  University of Pisa, where his father hoped he
  would study medicine.
• while at the University of Pisa, he began his
  study of the pendulum while, according to legend,
  he watched a suspended lamp swing back and forth
  in the cathedral of Pisa. However, it was not
  until 1602 that Galileo made his most notable
  discovery about the pendulum

http//en.wikipedia.org/wiki/Galileo_Galilei
The period is independent of the arc
http//galileo.rice.edu/bio/narrative_2.html
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Galileo Galilei (1564-1642)

• the telescope was invented in the Netherlands in
  1608 Galileo made one in 1609 with 3x
  magnification, and then made improved models up
  to 32x
• in 1610 he published an account of his telescopic
  observations of the moons of Jupiter, using this
  observation to argue in favor of the Copernican
  model of the cosmos against the Ptolemaic
  Aristotelian views
• when some argued that what he was seeing through
  the telescope was not reliable, he took them up a
  church tower in Venice and let them look at the
  city through his telescope

http//grus.berkeley.edu/jrg/CELT/gal_telescope.g
if
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Galileos Drawings of the Moon
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Galileos Drawings of Sunspots
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Sun Rotating
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Translation of Galileos Sidereus Nuncius
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Moons of Jupiter
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Rings of Saturn
Telescopic view
Galileos drawing
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Galileos Drawings of Phases of Venus
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Photographic Images of Phases of Venus
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Phases of Venus
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Ptolemaic vs. Copernican Models
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Galileos Inquest the Placing of Copernicus De
Revolutionibus on the Index
Friday, the twenty-sixth, 1616.  At the palace,
the usual residence of  Lord Cardinal Bellarmine,
the said Galileo, having been summoned and being
present before the said Lord Cardinal, was
commanded and enjoined, in the name of His
Holiness the Pope and the whole Congregation of
the Holy Office, to relinquish altogether the
said opinion that the Sun is the center of the
world and immovable and that the Earth moves nor
further to hold, teach, or defend it in any way
whatsover, verbally or in writing otherwise
proceedings would be taken against him by the
Holy Office which injunction the said Galileo
acquiesced in and promised to obey.  March 5,
1616. Therefore, in order that this opinion may
not insinuate itself any further to the prejudice
of Catholic truth, the Holy Congregation has
decreed that the said Nicolaus Copernicus, De
revolutionibus orbium, and Diego de Zuniga, On
Job, be suspended until they be corrected
http//www.law.umkc.edu/faculty/projects/ftrials/g
alileo/galileo.html
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Galileos Trial (1633)
Papal Condemnation (June 22, 1633). Whereas
you, Galileo, son of the late Vaincenzo Galilei,
Florentine, aged seventy years, were in the year
1615 denounced to this Holy Office for holding
as true the false doctrine taught by some that
the Sun is the center of the world and immovable
and that the Earth moves, and also with a
diurnal motion for having disciples to whom you
taught the same doctrine for holding
correspondence with certain mathematicians of
Germany concerning the same for having printed
certain letters, entitled "On the Sunspots,"
wherein you developed the same doctrine as true
and for replying to the objections from the Holy
Scriptures, which from time to time were urged
against it, by glossing the said Scriptures
according to your own meaning and in this
divers propositions are set forth, following the
position of Copernicus, which are contrary to the
true sense and authority of Holy Scripture
http//www.law.umkc.edu/faculty/projects/ftrials/g
alileo/galileo.html
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Galileo remained an Aristotelian in some ways

• Galileo never accepted Keplers elliptical orbits
  of the planets (published in 1609), considering
  the circle a "perfect" shape.
• He died in house arrest in 1642.
• On Oct. 31, 1992 Pope John II officially
  apologized for the Churchs treatment of Galileo
  (http//en.wikipedia.org/wiki/Pope_john_paul_
  II)

(http//en.wikipedia.org/wiki/Galileo_Galilei)
http//en.wikipedia.org/wiki/Astronomia_nova