Transcript Geocentric Model of Solar Systemx

https://www.youtube.com/watch?v=ofmi03d1U0s
PHENOMENON:
What did you observe?
What evidence do you
have?
OBJECTS:
Define the
system.
What
objects are
interacting?
MOTION:
Describe the motion that in
the model that explains
your observations
MODEL:
Diagram of the model
that
Describes the motion and
observations (evidence)
As viewed from Earth in
Greece 2000 years ago
Ancient Greek/ Aristotle:
Sun
Moon
Stars
(Milky
Way arm)
Ptolemy
Summarize the geocentric model:
Aristotle (350 B.C.)
Greek
• Formulated a picture of the solar system
that put Earth at its center with all the
other heavenly bodies orbiting around it.
• GEOCENTRIC model
• The orbits were perfect circles.
PHENOMENON:
What did you observe?
What evidence do you
have?
OBJECTS:
Define the
system.
What
objects are
interacting?
MOTION:
Describe the motion that in
the model that explains
your observations
MODEL:
Diagram of the model
that
Describes the motion and
observations (evidence)
Ancient Greek/ Aristotle:
Sun
Moon
stars
Ptolemy
Summarize the geocentric model:
The “Wanderers”
 The Greeks continued to watch the night sky,
 The Sun, moon, stars moved in a predictable orbit in
the sky.
 BUT, there were five “objects” that did not follow this
regular, predictable motion
 Once every year, they’d move BACKWARDS
(retrograde) for a month or two!!
 They “wandered”, thus called planetes
(Mercury, Venus, Mars, Jupiter, Saturn)
The retrograde (backward, looping) motion of Mars.
A composite image created by superimposing images taken on twenty-nine different dates.
Observations
Watch the animation and make observations
about the motions of the planets and the Sun.
Write these observations by the correct symbol for
the planet on your paper (opposite side of the
POM chart)
• http://www.davidcolarusso.com/astro/
Draw a BIRD’S-EYE-VIEW (as if you were looking
down at it) of all the planets and the sun as they
appeared in the animation. REMEMBER you are
drawing this as if you existed in Ancient Greece
and before technology told us what we know
about the planets and their positions and motion.
PHENOMENON:
What did you observe?
What evidence do you
have?
OBJECTS:
Define the
system.
What
objects are
interacting?
MOTION:
Describe the motion that in
the model that explains
your observations
MODEL:
Diagram of the model
that
Describes the motion and
observations (evidence)
Ancient Greek/ Aristotle:
Ptolemy
Sun,
Planets:
Mercury
Venus
Mars
Jupiter
Saturn
Summarize the geocentric model:
Whiteboard Time
Discuss your diagram with
your partner and draw a
diagram of a mutual BIRD’SEYE-VIEW that both of you
can agree upon. Place it
standing up on a lab table
when you are done.
Ptolemy (Greek)
A.D. 140
 He attempted to construct a model of the solar
system that explained the motions of the planets.
 The model had to be testable by predicting future
motion
What does this look like?
Ptolemy’s model of the Solar
System/Universe
Epicycle
To be continued….
His model explained the observed motion of the planets.
His model enabled them to predict the future motion of planets.
But it was way too complicated!
And it was not right.
http://www.youtube.com/watch?v=GevV1yvMJbc
History Channel (4 min)

http://www.youtube.com/watch?v=utH-GHH1FT8&feature=related
Ptolemy (3 min.)
PHENOMENON:
What did you observe?
What evidence do you
have?
Milky Way stars (constellations),
Sun, Moon, appear to rise in the
sky, move across the sky in an
arch or circle during the night/day
at different angles, then set.
(Animation)
All the planets appear to move
from right to left
All the planets loop backward
(retrograde)
Different planets make different
size loops: Mercury and Venus
have large loops, Saturn’ small
Sun doesn’t loop.
Jupiter and Saturn make small,
slow loop
OBJECTS:
MOTION:
Define the
Describe the motion that in
system.
the model that explains your
What objects
observations
are interacting? Historical explanations**
Earth
Moon
stars,
Sun
Earth
Planets
Sun
Sun, moon, planets, stars are orbiting
around the Earth (at the center) in
different orbits and orbital angles in
perfect circles.
GEOCENTRIC
Planets orbit counter-clockwise.
Closer planets are making larger loops
Farther planets are making smaller
loops
Big loop planets are closer to the
Fast planets have smaller orbits, slow
planets are making larger orbits
Measurements
**But Wrong!!
MODEL:
Diagram of the model that
Describes the motion and
observations (evidence)
Aristotle
Ptolomy
Page 588-
Solar System Models
GEOCENTRIC Models
HELIOCENTRIC Models
Ancient Greeks
300 B.C.-140 A.D.
Aristotle
Ptolemy
Europeans
1400’s
Copernicus / Galileo
Newton
Tycho Kepler
Brahe