The Greeks are well-known for their significant contributions in a variety of fields. They were more than just great philosophers. They were also outstanding scientists and mathematicians. In this module, we tackled about the several arguments for a spherical earth listed by Aristotle. (1) North Star. The North Star was thought to be fixed in place in the sky. However, when the Greeks traveled closer to the equator, such as Egypt, they noticed that the North Star is getting closer to the horizon. (2) Shape of the Sun and the Moon. Aristotle asserted that if the Moon and Sun were both spherical, then the Earth was spherical as well. (3) Disappearing Ships. If the Earth were flat, a ship traveling away from an observer would shrink and get smaller until it vanished. The Greeks, on the other hand, noticed that the ship shrank and that its hull vanished first, before the sail, as if it were being engulfed by water, until it vanished completely. (4) The Size of the Spherical Earth. Calculations were used by ancient scholars to prove the Earth's spherical shape and circumference. During their time, the most accurate size was given by Eratosthenes.

I have also learned about some of the Greek astronomers, as well as their findings and discoveries. These are: (1) Anaxagoras. He was able to explain the causes of the phases of the moon. (2) Aristotle, who argued that the earth is spherical in shape. (3) Eudoxus, who proposed a system of fixed spheres. (4) Aristarchus. He is the very first Greek to profess the heliocentric view. (5) Eratosthenes who has determined the first successful attempt of calculating the size of the earth. (6) Hipparchus. He developed a method for predicting the times of lunar eclipses to within a few hours. And; (7) Claudius Ptolemy who believed that the earth was the center of the universe.

Even before the advent of telescopes, ancient astronomers were able to observe different astronomical phenomena. But first, astronomy is the science of the universe outside of our planet. Moving on, in this module, I have learned about the various astronomical phenomena before the invention of telescopes. These are: (1) Rising and Setting of the Sun which are discovered by the Babylonian and Egyptian civilizations. (2) Phases of the Moon which are, new moon, first quarter, full moon, and third or last quarter. (3) Eclipses which has two types of eclipses, lunar eclipse and solar eclipse. The difference between the two was also tackled. And; (4) Daily and Annual Motion of the Star which states that the movement of different celestial bodies can be described as diurnal motion, annual motion, and precession of the equinoxes. And lastly, I have ascertained that Mercury, Venus, Mars, Jupiter, and Saturn were the planets discovered before the invention of the telescope. It was kind of interesting trivia because I never imagined how our ancestors discovered them without even using a telescope. They must be very smart and resourceful.

Taking everything into account, what our ancestors did in the past years, without even the help of advanced technology, has been a great help in better understanding the nature of the world in which we have lived and are currently living. It made us better understand the nature of the universe and widened our knowledge about the various aspects of the universe and our planet. They served as the basis of the current knowledge we have. They really played a significant role in the body of knowledge that we are still using and that is useful nowadays. Their theories, discoveries, and contributions have become a big part of cultivating and understanding the mystery of the world until now. They are indeed, the pioneers of science.