geocentric and helocentric

1
Geocentric modelheliocentric model
2
Geocentric model

• In astronomy, the geocentric model (also known
  as geocentrism, or the Ptolemaic system) is a
  description of the cosmos where Earth is at the
  orbital center of all celestial bodies.

3
Figure of the heavenly bodies 
4
Geocentric Model of the Universe
5
Two commonly made observations supported the idea
that Earth was the center of the Universe. The
stars, the sun, and planets appear to revolve
around Earth each day, making Earth the center of
that system. The stars were thought to be on
acelestial sphere, with the earth at its center,
that rotated each day, using a line through the
north and south pole as an axis. The stars
closest to the equator appeared to rise and fall
the greatest distance, but each star circled back
to its rising point each day.2 The second
observation supporting the geocentric model was
that the Earth does not seem to move from the
perspective of an Earth-bound observer, and that
it is solid, stable, and unmoving.
6
Did you know ?

• Our ideas about the solar system change as we
  find new evidence

7
heliocentric model

• The Heliocentric System. In a book called On the
  Revolutions of the Heavenly Bodies (that was
  published as Copernicus lay on his deathbed),
  Copernicus proposed that the Sun, not the Earth,
  was the center of the Solar System. Such a
  model is called a heliocentric system.

8
WHAT IS THE HELIOCENTRIC MODEL OF THE UNIVERSE?

• The Scientific Revolution, which took place in
  the 16th and 17th centuries, was a time of
  unprecedented learning and discovery. During this
  period, the foundations of modern science were
  laid, thanks to breakthroughs in the fields of
  physics, mathematics, chemistry, biology, and
  astronomy. And when it comes to astronomy, the
  most influential scholar was definitely Nicolaus
  Copernicus, the man credited with the creation of
  the Heliocentric model of the Universe.

9
Based on ongoing observations of the motions of
the planets, as well as previous theories from
classical antiquity and the Islamic World,
Copernicus proposed a model of the Universe
where the Earth, the planets and the stars all
revolved around the Sun. In so doing, he resolved
the mathematical problems and inconsistencies
arising out of the classic geocentric model and
laid the foundations for modern astronomy.
10
(No Transcript)
11
(No Transcript)
12
(No Transcript)
13
Modern astronomyradio telescope
14
(No Transcript)
15
Made by rabia ,rukhsar ,sadaf ,atika, saima

• Class 7th a

16
Thanks for listening