Physical Science SHS 14.3~4 Models of the Universe.pptx

Model of the universe

1. Lesson 14.3~4 Models of the Universe

2. describe the evolution of the early models of the planetary objects; and compare and contrast the prevailing early models of the planetary objects. 1 At the end of the lesson, you should be able to: 2

3. The history of the model of the universe transition from the geocentric to the heliocentric model over time. The heliocentric model places the sun as the center of the solar system and the planets orbit around it. The geocentric model has the earth at the center of the solar system.

4. Eudoxus of Cnidus proposed a model of the universe to explain the apparent opposite motion of some planets. (retrograde motion). He placed Earth at the center and explained that various spheres are needed to explain the observed movement of objects. The spheres spin around different axes on a steady motion. The sun’s sphere revolves around the earth once every 24 hours. Eudoxus and a Geocentric Universe

5. Eudoxus’ model of the universe.

6. Just like Eudoxus, Aristotle’s universe is geocentric which places the sun and other planetary objects around Earth. He added that the universe is finite in terms of space and eternal in time. In his model, the universe was spherical but infinite. Concentric spheres surrounded Earth, with objects following perfectly circular orbits that were guided by “souls” . Aristotle and a Finite, Eternal, and Geocentric Universe

7. Aristotle’s model of the universe.

8. Aristarchus of Samos was the first person to attempt to calculate the distance of the earth to the sun during the 3rd century. He conducted this by measuring the angle between the moon and the sun and applied the principles of trigonometry. The ratio between the distances is equivalent to the cosine of the angle. Aristarchus and the Distance to the Sun and Moon

9. Aristarchus and the Distance to the Sun and Moon Aristarchus principle in measuring the distance between the earth and the sun.

10. Aristarchus described Earth as a body that rotated daily around an axis and revolved annually around the sun. The stars were fixed in a large sphere with the sun at the center. Aristarchus and the Distance to the Sun and Moon Aristarchus’ model of the universe.

11. Ptolemy adapted Aristotle’s geocentric theory of the universe. Ptolemy’s idea is that the planets do not orbit in perfect circles around the earth. Ptolemy and Epicycles

12. Ptolemy proposed another model where the whole universe moved about a fixed, stationary Earth. He accounted for the apparent motions of the planets around the earth by assuming that each planet moved around a sphere called an epicycle . The center of the epicycle moved on a larger sphere called a deferent . Ptolemy and Epicycles

13. Ptolemy and Epicycles Ptolemy’s model of the universe.

14. He noted that the motion of the planet could be described by large loops where the planet moves in a retrograde motion. Ptolemy and Epicycles Ptolemy’s proposed epicycle movement of the planet.

15. Ptolemy’s model was able to predict the movements of the planets with certain accuracy but it was not able to explain the observable changes in the phases of Venus. Ptolemy and Epicycles

16. Nicolaus Copernicus introduced the concept of a heliocentric universe -- the sun is at its center. He explained that Earth is only one of the many planets that revolve around the sun. Copernicus and a Heliocentric Universe Copernican model of the universe.

17. Taking the apparent movement of the stars in the sky into account, he explained that Earth spins around its axis. His model was able to successfully explain the observed changes in the phases of Venus. Copernicus and a Heliocentric Universe

18. The heliocentric model places the sun as the center of the solar system and the planets orbit around it. The geocentric model has the earth at the center of the solar system and the sun together with all the other planets orbiting around it. 1 2

19. Ancient Greek astronomer, Eudoxus of Cnidus presented a mathematical theory of the universe model. Eudoxus of Cnidus proposed a model of the universe to explain the apparent opposite motion of some planets (called retrograde motion). Aristarchus of Samos is the first person to attempt to calculate the distance of the earth to the sun during the 3rd century BCE. 3 4

20. Roman astronomer, Ptolemy adapted Aristotle’s geocentric theory of the universe. Ptolemy’s idea is that the planets do not orbit in perfect circles around the earth. Some planetary objects like the Mars appear to move backwards first then move forward in large loops. Polish astronomer, Nicolaus Copernicus introduced the concept of a heliocentric universe where the sun serves as its center. He explained that Earth is only one of the many planets that revolve around the sun. 5 6

21. Complete the Venn diagram to compare the heliocentric and geocentric models of the solar system.

22. During the early times, the Catholic church believes that the geocentric model is true. If you had the chance to live during that period, how would you convince the church about the heliocentric model?

23. 1. Which BEST explains why the Earth is not disk-shaped? A. Stars are viewed differently when traveling north and south. B. The shadow cast by the Earth during a lunar eclipse is circular. C. The shadows cast in two different cities during a solstice differed in length. D. The only shape that cast a circular shadow in whatever direction is a sphere. DIRECTIONS: Read each question carefully. Write your answer on a separate sheet of paper.

24. 2. How long is the Earths revolution? A. 236.25 days B. 365 days C. 366.25 D. 366 days 3. What is the shape of the Earth as described by modern astronomy? A. elliptical B. hyperbolic C. oblate spheroid D. parabolic

25. 4. Who among the Greek philosophers measured the circumference of the Earth? A. Aristotle B. Anaxagoras C. Eratosthenes D. Homer 5. Because of Earth’s curvature, what can be observed about a ship approaching the horizon? A. It remains at the same apparent size. B. Its mast (top portion) disappears first. C. Its hull (bottom portion) disappears first. D. It becomes smaller and smaller until it disappears.

26. 6 . Which of the following phenomena occurs when the moon is between the sun and the earth and the moon is partially or complete blocks out the sun? A. Lunar Eclipse C. Phases of the Moon B. Solar Eclipse D. Motion of the Stars 7 . Which of the following phenomena occurs when the earth casts its shadow on the moon and the Earth is between the sun and moon? A. Lunar Eclipse C. Phases of the Moon B. Solar Eclipse D. Motion of the Stars

27. 8 . About how many days does the path and appearance of the moon changes as observed by ancient people? A. 27.5 days B. 29.5 days C. 30 days D. 31 days 9 . Which of the following is not a pre-telescope observed phenomena? A. Lunar Eclipse C. Motion of the Stars B. Phases of the Moon D. Visibility of Uranus and Neptune

28. 10 . Which of the following became the basis for ancient calendar? A. Lunar Eclipse B. Phases of the Moon C. Motion of the Stars D. Visibility of Uranus and Neptune