The document discusses theories about the formation of the solar system. It describes the Nebular Hypothesis theory, which states that the solar system originated from a large cloud of gas and dust that contracted due to gravity, forming denser pockets that began rotating and heating up. Most material ended up in the center to form the sun, while the rest flattened into a disk that circled it and formed the planets. It also describes the earlier Encounter Hypothesis theory and problems with it, and discusses geocentric and heliocentric models of the structure of the early solar system.

1. EARTH AND LIFE SCIENCE
LESSON 2:
LESSON 2:
THE SOLAR
THE SOLAR
SYSTEM
SYSTEM

2. LESSON OBJECTIVES
LESSON OBJECTIVES
At the end of the lesson, the students
should be able to explain how the solar
system formed
How did the solar system
form?
ESSENTIAL QUESTION:
ESSENTIAL QUESTION:

3. A gravitationally bound
system consisting of
the Sun and everything
that orbits it.
THE SOLAR
THE SOLAR
SYSTEM
SYSTEM

4. Are you ready to learn?
THEORIES ABOUT
THEORIES ABOUT
THE ORIGIN OF THE
THE ORIGIN OF THE
SOLAR SYSTEM
SOLAR SYSTEM

5. THE ENCOUNTER
HYPOTHESIS
THEORY 1
THEORY 1

6. THE ENCOUNTER HYPOTHESIS
THE ENCOUNTER HYPOTHESIS
ACCORDING TO THE ENCOUNTER
HYPOTHESIS, ABOUT 5 MILLION YEARS
AGO, A ROGUE STAR PASSED CLOSE TO
THE SUN AND STRIPPED MATERIALS
(HOT GASES) FROM BOTH THE SUN AND
THE ROGUE STAR.

7. THE ENCOUNTER HYPOTHESIS
THE ENCOUNTER HYPOTHESIS
THE HOT GASES CONTINUED TO SPIN
IN THE SAME DIRECTION AS THE SUN
AND COMBINED INTO SMALLER
LUMPS WHICH FORMED THE
PLANETS.

8. THE ENCOUNTER HYPOTHESIS
THE ENCOUNTER HYPOTHESIS
THIS HYPOTHESIS WAS ABLE TO
EXPLAIN WHY ALL THE PLANETS
REVOLVE IN THE SAME DIRECTION
AND WHY THE INNER PLANETS ARE
DENSER THAN THE OUTER ONES.

9. THE ENCOUNTER HYPOTHESIS
THE ENCOUNTER HYPOTHESIS
ONE IS THAT HOT GAS EXPANDS,
NOT CONTRACTS. SO LUMPS OF HOT
GAS WOULD NOT FORM PLANETS.
TWO MAJOR PROBLEMS WITH THE
ENCOUNTER HYPOTHESIS:

10. THE ENCOUNTER HYPOTHESIS
THE ENCOUNTER HYPOTHESIS
THE SECOND IS THAT ENCOUNTERS
BETWEEN STARS ARE EXTREMELY RARE,
SO RARE AS TO BE IMPROBABLE IN THE
LIFETIME OF THE UNIVERSE
TWO MAJOR PROBLEMS WITH THE
ENCOUNTER HYPOTHESIS:

11. THE NEBULAR
HYPOTHESIS
THEORY 2
THEORY 2

12. A NEBULA IS AN INTERSTELLAR
CLOUD OF GAS AND DUST.
MOST OF A NEBULA'S MASS IS
MADE OF HYDROGEN AND HELIUM,
THE SIMPLEST ELEMENTS AND THE
FIRST TO FORM AFTER THE BIG
BANG.
THE NEBULAR HYPOTHESIS
THE NEBULAR HYPOTHESIS

13. THIS HYPOTHESIS STATES THAT
THE ENTIRE SOLAR SYSTEM
STARTED AS A LARGE CLOUD
OF GAS THAT CONTRACTED
DUE TO SELF-GRAVITY.
THE NEBULAR HYPOTHESIS
THE NEBULAR HYPOTHESIS

14. FROM THE COLLAPSE, POCKETS OF
DUST AND GAS BEGAN TO
COLLECT INTO DENSER REGIONS.
AS THE DENSER REGIONS PULLED
IN MORE AND MORE MATTER, IT TO
BEGIN ROTATING, AND HEATING
UP.
THE NEBULAR HYPOTHESIS
THE NEBULAR HYPOTHESIS

15. MOST OF THE MATERIAL ENDED
UP IN A BALL AT THE CENTER
WHILE THE REST OF THE
MATTER FLATTENED OUT INTO
DISK THAT CIRCLED AROUND
IT.
THE NEBULAR HYPOTHESIS
THE NEBULAR HYPOTHESIS

16. Are you ready to learn?
THEORIES ABOUT
THEORIES ABOUT
SOLAR SYSTEM'S
SOLAR SYSTEM'S
STRUCTURE
STRUCTURE

17. GEOCENTRIC MODEL OF
THE PLANETARY SYSTEM
SOLAR SYSTEM'S STRUCTURE
SOLAR SYSTEM'S STRUCTURE

18. THE GEOCENTRIC MODEL
THE GEOCENTRIC MODEL
ALSO KNOWN AS GEOCENTRISM
EXEMPLIFIED BY THE PTOLEMAIC
SYSTEM
EXODUS, ARISTOTLE, AND CLAUDIUS
PTOLEMY WERE THE THREE
PERSONALITIES ATTRIBUTED TO THIS
THEORY.

19. THE GEOCENTRIC MODEL
THE GEOCENTRIC MODEL
THIS THEORY EXPLAINS THAT
THE UNIVERSE CONSISTED OF
AN EARTH SURROUNDED BY THE
SUN, THE MOON, AND THE
STARS.

20. G
G
E
E
O
O
C
C
E
E
N
N
T
T
R
R
I
I
C
C
M
M
O
O
D
D
E
E
L
L

21. THE HELIOCENTRIC MODEL
THE HELIOCENTRIC MODEL
ALSO KNOWN AS HELIOCENTRISM
A THEORY THAT WAS PROPOSED BY
NICOLAUS COPERNICUS, A POLISH
ASTRONOMER.
HE FIRST PUBLISHED THE HELIOCENTRIC
SYSTEM IN HIS BOOK: DE REVOLUTIONIBUS
ORBIUM COELESTIUM, "ON THE REVOLUTIONS
OF THE HEAVENLY BODIES," WHICH
APPEARED IN 1543.

22. THE HELIOCENTRIC MODEL
THE HELIOCENTRIC MODEL
A HELIOCENTRIC SYSTEM EXPLAINS
THAT THE SUN IS AT THE CENTER OF
THE PLANETARY SYSTEM. THIS
MEANS THAT THE PLANETS REVOLVE
AROUND A FIXED SUN.

23. H
H
E
E
L
L
I
I
O
O
C
C
E
E
N
N
T
T
R
R
I
I
C
C
M
M
O
O
D
D
E
E
L
L

24. Hope you had fun!
THANK YOU FOR
THANK YOU FOR
LEARNING WITH ME!
LEARNING WITH ME!