The Copernican Revolution

Question 1

The idea that Earth was the center of the universe and
was motionless.

Answer 1

Geocentrism

Question 2

He believed to the idea was similar to Ptolemy that the Earth is motionless but celestial
bodies move around it. Planets move in “epicycles” which are circles concentric
to another circle around the Earth called “deference”. Hence, planets follow a uniform circular motion

Answer 2

Aristotle

Question 3

The idea that Earth
and planets revolve around a relatively stationary Sun at the center of
the Solar System. The word “helios” in Greek means “sun.” Heliocentric
means that the sun is at the center.

Answer 3

Heliocentrism

Question 4

He attested the idea
that the Sun is the center of the universe where planets revolve around it
while other celestial bodies such as the moon orbit the Earth.

He did this through “thought Experiment”

He published a book called “ “On the revolutions of the Heavenly spheres” during sometime 16th century.

Answer 4

Nicolaus Copernicus (1473 – 1543)

Question 5

Important Points of the Copernican Model

Answer 5

• The Earth is not
  at the center of everything.
• Only the Moon orbits Earth.
• All the spheres orbit the Sun. Spheres means the planets.
• The stars are very much farther away than the Sun.
• The motion of the stars is due to the Earth rotating on its axis; The
  retrograde (clockwise) and forward motions of planets is caused by the
  Earth’s motion.
• The motion of the Sun is the result of the Earth’s motions. (rotation and
  revolution

Question 6

The Copernican principles

Answer 6

*The Copernican Principle is a basic statement in physics that there should be no ``special’’ observers. The Earth has no a privileged position in the universe; it is not stationary as stated in the Heliocentric model of the solar system.

Question 7

He’s the responsible for the discovery of a supernova.

He also develop a comprehensive observations of the skies, before the discovery of the telescope

Extensive measurements of the position of Mars in
the skies; these data led in time to Kepler’s three laws
of planetary motion

Mars was not a circle but an ellipse;

He proposed an intermediate model [Tychonic system]
( Earth was the center but other planets are allowed to revolve around it)

• He believed in a model of the Universe with the Sun (rayed disk) orbiting the Earth (black dot), but the other planets (symbols) orbiting the Sun.

Answer 7

Tycho Brahe

Question 8

He used Brahe’s inputs to prove the Copernican Model

• He’s laws provide accurate evidences to Newton’s laws of motion
  and universal gravitation.

Answer 8

Johannes Kepler

Question 9

Johannes Kepler’s Laws of Planetary
Motion

Answer 9

• 1 st Law: Law of Ellipse: that the planets move in an ellipse (a squashed circle) with the Sun at one focus point, offset from the center.
• 2nd law: Law of Equal Areas : the planet must move more quickly
  when it is near the Sun, but more slowly when it is farthest from the
  Sun
• 3rd law: Law of Periods: there is a precise mathematical relationship
  between a planet’s distance from the Sun and the amount of time

Question 10

He invented the Telescope

• Individual stars within the Milky
  Way
• Phases for Venus, like those of the
  Moon
• Moons orbiting Jupiter (Io, Europa,
  Ganymede and Callisto)

Mountains and volcanoes on the Moon Sunspots, which moved, on the Sun

Answer 10

Galileo Galilei
(1564 – 1642)