Astronomy is the study of objects beyond Earth, including planets, stars, galaxies and the universe itself. It began thousands of years ago as people observed patterns in the sky and tried to make sense of natural phenomena. Early astronomers also practiced astrology and used the movements of celestial objects to predict events and seasons. Key figures like Copernicus, Galileo and Ptolemy advanced our understanding through careful observation and mathematical theories, though some of their ideas faced religious opposition. Advances in astronomy have continued with new instruments allowing for important discoveries about objects in space.

2. What is astronomy?
Astronomy is a study of virtually everything
beyond earth. The academic discipline includes
studying planets, solar systems, stars, galaxies,
comets, asteroids, nebulae, moons and the
Universe itself.

3. Astronomy is a visually - based science. The
skill of careful observation is essential to
understanding and discovery.

4. When did Astronomy began?
Many astronomical skills
were developed as long as
5,000 years ago. Before
written history began,
people had noticed the
interrelationships between
the Sun, Moon and the
Earth.

5. When did Astronomy began?
When there were no answers for natural
occurrences, observers concluded that it was
caused by actions of the gods.

6. Astrology
Astrology and its astrologers
were cosmos based, religious
fortune tellers and “the gods’ will”,
messengers. They closely studied
the stars, planets, the moon and
sun and then tried to derive
meaning for their movements. At
times important decisions (war,
marriages, coronations, etc.),
were timed because of
predictions put forth by these
astrologers.

7. Astrology
Some of their observations were quite helpful. They
could advise when to plant and harvest. They could
determine when the next full moon night would
occur. For those who lived near coasts, they could
predict tides. They learned to use star patterns for
day and night time navigation.

8. Importance of Astrology/Astronomy
1. Developed skills of predicting weather patterns
and seasons allowed man to time harvests. From
this, each man no longer had to just hunt, gather
and maintain flocks. Agriculture was developed,
creating greater food supplies this led to larger
populations, spare time to build, invent and
develop communities.

9. Importance of Astrology/Astronomy
2. Star observation and mapping allowed for the
navigation of new land and sea routes.
3. Trade and exchanges of ideas developed
between cultures. Over time, ancient civilizations
gained wealth, power and improved technology
based on the increased amounts of food and
trade, that was inspired by studying the cosmos.

10. Importance of Astrology/Astronomy
4. Mathematics was integral to the advancement of
astronomical studies. The ancient people of
Egypt and Greece developed algebra and
geometry. Through these math skills and little
else, a Greek citizen named Aristarchus, in 270
BC first figured out how far the moon was from
the earth.

11. Importance of Astrology/Astronomy
5. This brings us to another important component:
philosophy. Greek philosophers developed this
rational process of thought called SCIENTIFIC
METHOD.
Scientific Method- a method of procedure that has
characterized natural science since the 17th century,
consisting in systematic observation, measurement,
and experiment, and the formulation, testing, and
modification of hypotheses.

12. Astrology, as found today, is no longer dominant over
astronomy. It is looked upon as a superstition that
tries to tie the cosmos to fortune telling, personality
traits and daily life.

13. Ptolemy
Claudius Ptolemaeus was a
Greek astronomer and
mathematician who lived long
ago- from about 100 to 170 AD.
Western Influence on Astronomy

14. His main idea known as Ptolemaic System was that
the planet Earth was the center of the universe and
all of the other planets, stars and the Sun revolved,
or circled, around it.
This theory is also known as
GEOCENTRIC
GEO= earth
CENTRIC= center
Western Influence on Astronomy

15. Ptolemy’s theory was supported
by the Catholic Church
However, Ptolemy’s theory was
challenged by two men and one
instrument
Western Influence on Astronomy

16. Nicholas Copernicus
a Polish mathematician,
was educated in
medicine, mathematics,
astronomy and astrology
in Poland and in
renaissance Italy.
Western Influence on Astronomy

17. Copernicus proved through math and
observations the earth rotates on an axis
and that the earth circles the sun, not
visa versa.
Western Influence on Astronomy

18. In it he called the heliocentric system the logical
explanation of the earth’s relationship to the sun.
HELIO= SUN
CENTRIC= CENTER
Western Influence on Astronomy

19. Contrary to Ptolemy’s theory, the Protestant
and Catholic Churches did not support
Copernicus theory
Western Influence on Astronomy

20. Galileo Galilee
Galileo, an Italian born 21 years after the
death of Copernicus, studied medicine but
also had a keen interest in mathematics and
astronomy.
Western Influence on Astronomy

21. his most famous invention was a
telescope that could magnify up to
twenty times what can be seen by
the naked eye. He searched the
skies and even closely observed
the sun. Galileo made significant
discoveries concerning the Moon
and Jupiter.
Western Influence on Astronomy

22. Galileo’s discovery during his time:
 Galileo thought he saw oceans or seas on the
surface of the Moon. These areas he named:
“mare” (sea in Latin.) which still called by the
same names today, even though there are no
seas on the Moon.
 He found spots on the sun.
Western Influence on Astronomy

23.  He observed a supernova, (exploding star).
 He found four moons circling Jupiter.
Western Influence on Astronomy

24. Galileo published his works concerning the
verification of the heliocentric system and
ended up in the Inquisition, a court held by the
Catholic Church to try people accused of
religious heresies* that run counter to church
doctrine.
Heresy- belief or opinion contrary to orthodox
religious (especially Christian) doctrine.
Western Influence on Astronomy

25. He was tried twice and the second time he was
convicted and spent the rest of his life under house
arrest. He died in 1638, at the age of 74, a blind
man.
Western Influence on Astronomy

26. REMEMBER!!!
Don’t make the mistake Galileo made when
he studied the sun through a telescope!
Western Influence on Astronomy

27. As time went on, the Catholic and
Protestant churches accepted the new
discoveries and loosened religious
control over scientific research and their
findings.
Western Influence on Astronomy

28. With the use of math and telescopes many
discoveries have been made. All the planets were
located. Many asteroids and comets were not only
tracked but their physical characteristics were better
understood.