2. MOTION IN THE SKY
•Dating back to 1800 B.C., the Babylonians were among the first
civilization to document the movements of the sun and the moon.
They maintained a very detailed record of these motions including a
daily, monthly, and yearly position of the celestial bodies.
• This information was initially of mystical value used to warn the king
about possible catastrophic events. It is said that the first
appearances of the famous Hailey’s comet were documented by the
Babylonians and it is also them who first divided the sky into zones.
3. PATTERNS OF STARS AND CONSTELLATION
•What is a constellation?
A constellation is a group of visible stars that form a
pattern when viewed from Earth. The pattern they form
may take the shape of an animal, a mythological creature,
a man, a woman, or an inanimate object such as a
microscope, a compass, or a crown.
•How many constellations are there?
The sky was divided up into 88 different constellations in
1922. This included 48 ancient constellations listed by the
Greek astronomer Ptolemy as well as 40 new
constellations.
4. USES OF CONSTELLATION
•Constellations are useful because they can help
people to recognize stars in the sky. By looking for
patterns, the stars and locations can be much easier
to spot.
•The constellations had uses in ancient times. They
were used to help keep track of the calendar. This
was very important so that people knew when to
plant and harvest crops.
5. •Another important use for constellations
was navigation. By finding Ursa Minor it is
fairly easy to spot the North Star (Polaris).
Using the height of the North Star in the
sky, navigators could figure out their
latitude helping ships to travel across the
oceans.
6. GEOCENTRIC VIEWS
•Humans have come up with several models in an effort to
understand the universe. Before the invention of the
telescope, they had to rely on their senses for a picture of
the universe with much philosophical and religious
symbolism.
•Around 600 BCE, Thales of Miletus proposed that Earth is
a disk floating on water.
•In 520 BCE, Anaximander, also from Miletus, suggested
that Earth is a cylinder and that its surface is curved.
7. •The Pythagorean Model
•Acknowledged to be the first to assert that Earth is
round, and that the heavenly bodies move in circles.
•The Earth is at rest at the center of the universe and
everything rotates around it.
•He considered that the motions of the planets were
mathematically related to musical sounds and
numbers. These ideas are called “The Music of the
Spheres.”
8. PRESENT OF COMETS
•Comets have inspired dread, fear, and awe in many
different cultures and societies around the world
and throughout time. They have been branded with
such titles as "the Harbinger of Doom" and "the
Menace of the Universe." They have been regarded
both as omens of disaster and messengers of the
gods.
9. •When people living in ancient cultures looked up, comets
were the most remarkable objects in the night sky.
Comets were unlike any other object in the night sky.
Whereas most celestial bodies travel across the skies at
regular, predictable intervals, so regular that
constellations could be mapped and predicted, comets'
movements have always seemed very erratic and
unpredictable. This led people in many cultures to believe
that the gods dictated their motions and were sending
them as a message
10. •Which planets are easily
seen in the sky without the
aid of telescopes?
11. •Mercury, Venus, Mars, Jupiter, and Saturn are easily seen
in the sky without the aid of telescopes. These planets can
be easily confused with stars and are only seen at specific
times of the day. The best time to look for these planets
would be before sunrise and after sunset.
•Even before the invention of the telescope, ancient
people have already observed different astronomical
phenomena. The most observable objects in the sky are
the sun and moon.
12. • Babylonian and Egyptian civilizations used a primitive version of
a sundial, called gnomon, in systematically observing the motion
of the sun. By looking at the shadows that the gnomon casts,
they were able to observe that the sun rises in the eastern part
of the sky, reaches its highest point in midday, and sets in the
western part of the sky.
• Also, they recorded that the points where the sun rises and sets
on the horizon varies over a year and these variations happen
periodically. They observed that these variations are related to
weather and so concluded that seasonal changes in climate
happen during a course of one year.
13. Phases of the Moon
•Ancient people have observed that the moon
changes its path and its appearance within a
period of 29.5 days. They observed that the
moon changes its appearance from thin semi-
circular disk to full circular disk. These phases
of the moon is the basis of ancient calendars.
14. Lunar Eclipse
• Besides their observation in the different phases of the moon, they also
noticed that there are times when the moon or part of it seemed to be
covered by a shadow for a brief moment. A lunar eclipse occurs when the
Earth casts its shadow on the moon when the Earth is between the Sun
and the Moon.
• A phenomenon such as this is known as a lunar eclipse wherein the moon
changes into a dark or blood red color.