Physical-Science-SHS Q2 Mod1 Earth-is-Not-the-Center-of-the-Universe PDF

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Physical ScienceQuarter II – Module 1:Earth is Not the Center of theUniversePhysical Science – Senior High School Quarter 2– Module 1: Earth is Not the Center of the Universe First Edition, 2020Republic Act 8293, section 176 states that: No copyright shall subsist in any work of the Government of th...

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Physical Science Quarter II – Module 1: Earth is Not the Center of the Universe

Physical Science – Senior High School Quarter 2– Module 1: Earth is Not the Center of the Universe First Edition, 2020 Republic Act 8293, section 176 states that: No copyright shall subsist in any work of the Government of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit. Such agency or office may, among other things, impose as a condition the payment of royalties. Borrowed materials (i.e., songs, stories, poems, pictures, photos, brand names, trademarks, etc.) included in this module are owned by their respective copyright holders. Every effort has been exerted to locate and seek permission to use these materials from their respective copyright owners. The publisher and authors do not represent nor claim ownership over them. Published by the Department of Education – Region XI Regional Director: Evelyn R. Fetalvero Assistant Regional Director : Maria Ines C. Asuncion Development Team of the Module Writers: Maria Felez B. Matignao, Verna Flor A. Decolas Editors: Joyce C. Dura, Rovie C. Maturan, Althea S. Llameg Reviewers: Melbon Ryn M. Gamaya, Marian Hista Villacrusis, Ana Lorma A. Dahiroc Illustrator: Kier Taña, Daryl L. Escobar Layout Artist: Russellier C. Matas, Arlene U. Lastimoso Template Developer: Neil Edward D. Diaz Management Team: Evelyn R. Fetalvero

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Physical Science Quarter II – Module 1: Earth is Not the Center of the Universe

Introductory Message For the facilitator: As a facilitator, you are expected to orient the learners on how to use this module. You also need to keep track of the learners' progress while allowing them to manage their own learning at home. Furthermore, you are expected to encourage and assist the learners as they do the tasks included in the module.

For the learner: As a learner, you must learn to become responsible of your own learning. Take time to read, understand, and perform the different activities in the module. As you go through the different activities of this module be reminded of the following: 1. Use the module with care. Do not put unnecessary mark/s on any part of the module. Use a separate sheet of paper in answering the exercises. 2. Don't forget to answer Let Us Try before moving on to the other activities. 3. Read the instructions carefully before doing each task. 4. Observe honesty and integrity in doing the tasks and checking your answers. 5. Finish the task at hand before proceeding to the next. 6. Return this module to your teacher/facilitator once you are done. If you encounter any difficulty in answering the tasks in this module, do not hesitate to consult your teacher or facilitator. Always bear in mind that you are not alone. We hope that through this material, you will experience meaningful learning and gain deep understanding of the relevant competencies. You can do it!

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Let Us Learn Astronomy started in Greece's ancient civilization through the great minds of Pythagoras, Anaxagoras, Plato, Aristotle, and Eratosthenes. Their notions on the Universe pave the way for the Ptolemaic, Copernican, and Tychonic model of the cosmos long before the telescope's invention. This Self-Learning Module (SLM) will walk you through the necessary concepts on the evidence that the Earth is not the center of the Universe. Specifically, this module contains three lessons and its subtopics. Lesson 1: The Spherical Earth 1.1: Greek Philosophers and their Arguments Lesson 2: Astronomical Phenomena Before Telescopes Lesson 3: Brahe's Innovation 3.1: Tycho Brahe 3.1.1 Tychonic Model 3.2: Johannes Kepler At the end of this SLM, you can: 1) explain how the Greeks knew that the Earth is spherical (S11/12PS-IVa38); 2) cite examples of astronomical phenomena known to astronomers before the advent of telescopes (S11/12PS-IVa-41); and 3) explain how Brahe's innovations and an extensive collection of data in observational astronomy paved the way for Kepler's discovery of his laws of planetary motion (S11/12PS-IVb-44).

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Let Us Try Direction: Read each item carefully. Choose the letter of the correct answer. Write your answer on a separate sheet of paper. 1. Which of the following is the shape of Earth in modern astronomy? A. cylinder C. oblate spheroid B. flat disc D. round 2. Who argued that the Earth should be a sphere because a sphere is a perfect form. A. Aristotle C. Plato B. Eratosthenes D. Pythagoras 3. What shape of an object produces a circular shadow? A. cube C. flat disk B. cylinder D. sphere 4. How long is a month of lunar phases? A. 14 days C. 29.5 days B. 27.3 days D. 365 days 5. Which refers to the group of constellations through which the Sun appears to move? A. ecliptic C. solstice B. equinox D. zodiac 6. What astronomical phenomenon wherein the Moon temporarily blocks the Sun's light and casts a shadow on Earth. A. Annular Eclipse C. Lunar Eclipse B. Hybrid Eclipse D. Solar Eclipse 7. What do Tycho Brahe believes to be the center of our planetary system? A. Earth C. Moon B. Mars D. Sun 8. Who was Tycho's famous assistant? A. Aristotle C. Isaac Newton B. Galileo Galilei D. Johannes Kepler 9. What model of the cosmos refers the Sun being the center of the universe? A. Copernican C. Ptolemaic B. Geo-heliocentric D. Tychonic 10. What did Tycho discover in 1572? A. Andromeda B. Great Comet C. Nova Stella D. Saturn's Rings

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Lesson

1

The Spherical Earth

Today, we know that the Earth is an oblate spheroid– flattened at the poles and has bulging equators. Through technology, human beings like us were able to travel to outer space. The International Space Station orbits the Earth and takes photographs. Photographs taken at different angles show that the Earth is spherical. However, the idea that the Earth was spherical started in the ancient Greek civilization.

rth This lesson will walk you through Greece's great thinkers as they convince people that the Earth is spherical with their arguments.

Let Us Study Perform Activity 1 to enlighten you on how Greek philosophers argue that the Earth is spherical. Activity 1: Shadows Direction: Study the figures below, then answer the guide questions on your answer sheet.

Figure 1

Figure 2

Guide Questions: 1. What shadow is cast in Figure 1? Figure 2? 2. Which of the following objects cast a circular shadow? 3

Lesson 1.1 Greek Philosophers and their Arguments Early Greek philosophers believed that the Earth was spherical in shape. The following are the philosophers who believed that Earth is spherical.

Aristotle (384 -322 BC)

Anaxagoras (500 - 430 BC)

Pythagoras (500 BC) Philosopher Pythagoras

Anaxagoras

Plato

Aristotle

Eratosthenes

Plato

Eratosthenes (276 – 194 BCE)

Arguments on Spherical Earth He believed circles and spheres to be perfect forms suggested that Earth should be a sphere just like that of the Moon's shape. He supported Pythagoras' idea on a spherical Earth. He observed that the Earth's shadow was reflected on the Moon's surface during a lunar eclipse. The reflected shadow was circular, and the sphere can only cast a circular shadow. He adopted the idea of a spherical Earth in his 4th and final dialogue Phaedo, given in a crowd and somewhat led to a broader circulation 400 BC. He presented ideas about a spherical Earth base on the position of the North Star, phases of the Moon, shape of the Sun and Moon, and ship's disappearance when they sail to the horizon. He argued that the Earth is spherical through the difference of the shadows cast at Alexandria and Syene at the same time of the day.

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Aristotle summarized and cited convincing arguments that the Earth must be round during his time. First, as the Moon emerges from Earth's shadow during the Moon's eclipse, the shape of the shadow seen on the Moon is always round. As shown in Activity 1, only a spherical object always produce a round shadow. If the Earth is a disk, then there would be occasions that the sunlight would strike on it edge-on, and its shadows on the Moon would be a line. Second, the North Star has been widely accepted as a fixed star in the sky, but when people traveled towards the equator, the star can be seen closer to the horizon. On a flat Earth, everyone would see the same stars overhead. The only possible reason is that the traveler must have moved over a curved surface on Earth, showing the North Star from a different angle. Lastly, if Earth was flat, then a huge ship traveling to the horizon should become smaller and smaller until it disappeared. However, the Greeks observed that the ship became smaller. Its hull disappeared first before the sail as if it sinks underwater until it completely disappeared. Eratosthenes strengthens Aristotle's argument that the Earth is spherical through his observation and calculations. Eratosthenes was living in Alexandria, Egypt. One day he was told that on the first day of summer in Syene, Egypt, sunlight struck the bottom of a vertical well at noon. This indicates that the Sun is directly over the well in Syene. At the same time in Alexandria, he observed the shadow cast by the column. He saw that the Sun was not directly overhead but was slightly south of the column. This indicates that the sunlight at Alexandria strike at a 7 o angle. If the Earth was flat regardless of the location, both should have the same circumstance simultaneously. Both the well in Syene and the column in Alexandria should either cast a shadow or none at all that summer.

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Let us Practice Direction: Match arguments on spherical Earth in column A to that of the philosophers in column B. Write only the letter of your answer. A

B

1. The difference of shadows cast at Alexandria and Syene 2. Earth should be a sphere because a sphere is a perfect form. 3. Cited that the North Star should be seen at the same time if the Earth was flat. 4. The first to observe that the shadow cast by Earth during lunar eclipse is circular. 5. Spread the idea of spherical Earth through his dialogue Phaedo

A. Anaxagoras B. Aristotle C. Eratosthenes D. Plato E. Pythagoras

Let Us Practice More Direction: True or False. Write T if the statement is true and change the underlined word/s if it is incorrect. Do this on a separate answer sheet. 1. The Earth should be a sphere because the Earth's shadow to the Moon is always round during the lunar eclipse. 2. The North Star is used as an argument to prove that the Earth is spherical as it can be seen at a fixed position at different locations. 3. When ships travel on the horizon, the hulls disappeared first before the sail as if it sinks. 4. Eratosthenes observed that the Sun is directly overhead at Syene and at 7o at Alexandria. 5. The Earth is flat.

Let Us Remember Key Concepts  The Greek philosophers who believed that the Earth was spherical are Pythagoras, Anaxagoras, Plato, Aristotle, and Eratosthenes.  Aristotle Arguments o The shape of the shadow of the Earth seen on the Moon is always round during lunar eclipse

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o The North Star can be seen at a different position at a different location. o The ship's hulls disappeared first before the sail. It sinks underwater until it completely disappeared as ships travel on the horizon.  Eratosthenes o The difference between the shadow cast at Alexandria (7o) and Syene (0o) proves that the Earth was spherical.

Let Us Assess Direction: Read each item carefully. Choose the letter of the correct answer. Write your answer on a separate sheet of paper. 1. Which of the following is the shape of Earth in modern astronomy? A. cylinder C. oblate spheroid B. flat disc D. round 2. Which of these civilizations made contributions to our understanding of astronomy and celestial objects? A. Babylonian C. Egyptian B. Chinese D. Greeks 3. Which of the following can be observed of a cruising ship if Earth is flat? A. It will not change its size. B. It will become bigger and bigger C. It will become smaller and smaller until it disappears. D. It will shrink then only the sail will be visible until it completely disappears. 4. Who argued that the Earth should be a sphere because a sphere is a perfect form. A. Aristotle C. Pythagoras B. Eratosthenes D. Plato 5. What shape of an object produces a circular shadow? A. cube C. flat disk B. cylinder D. sphere 6. Which of the following is NOT part of the group? A. Anaxagoras C. Eratosthenes B. Archimedes D. Pythagoras 7. What was Aristotle's argument on the location of the North Star? A. The North Star can only be seen at the North Pole. B. The North Star has a fixed position regardless of the location of the viewer. C. The North Star is seen to be on the horizon if the traveler went southwards. D. The North Star is seen to be just above the celestial pole even if the traveler went southwards. 7

8. How did Plato contribute to the spread of the idea that the Earth is a sphere? A. By observing the lunar eclipse. B. By delivering his dialogue entitled Phaedo. C. By calculating the distance between Alexandria and Syene. D. By citing that the North Star is seen at a different position in the sky as the traveler moves southwards. 9. Which of the following pairing is correct? I. Aristotle II. Eratosthenes III. The shape of the shadow of the Earth seen on the Moon is always round during lunar eclipse IV. The difference between the shadow cast at Alexandria (7 o) and at Syene (0o) proves that the Earth was spherical V. The North Star can be seen at a different position at a different location. A. I and IV C. II and III B. I and V D. II and V 10. According to Eratosthenes, which explains why a vertical stick casts a shadow in Alexandria but not in Syene? I. The Sun is directly overhead in Syene and about 7o in Alexandria II. The Sun is directly overhead in Alexandria and about 7o Syene. III. The light rays coming from the Sun are parallel, and the Earth is curved. IV. The light rays coming from the Sun are curved, and the Earth is flat. A. I only B. II only

C. I and III D. II and I

Let Us Enhance Eratosthenes calculated the circumference of the Earth through his calculations. He measured the distance in Alexandria to be 5000 stadia north of Syene. (The stadium was a Greek unit of length, derived from the length of the racetrack in a stadium.) One (1) stadium is about 0.167 km today. Remember in our discussion that from Alexandria to Syene, there is a curvature of 7o. This means that if the Earth was a sphere, there is 360o circumference. Given these values, calculate the circumference of the Earth in kilometers through the measurements of Eratosthenes. 8

Given:

5000 stadia – 1 stadium 7o 360o -

Ask:

Circumference in kilometers = ?

Solution:

(1) Convert 5000 stadia to kilometers (2) Let x be the circumference of the Earth in kilometers (3) Use ratio and proportion*

Alexandria to Syene in stadia 0.167 km angle between Alexandria and Syene Total circumference of the Earth in degrees

*Clue: Angle between Alexandria and Syene is to the distance in Alexandria to Syene in kilometers is equal to 360o is to the circumference of the Earth in kilometers Guide Questions: 1. Is the measurement of Eratosthenes the same value as that of the known value of the Earth's circumference, which is 40 000 km? If it is not, is it smaller or larger? 2. Is the difference between Eratosthenes' calculation and the known value of the Earth's circumference small or huge? 3. What can you say about the ingenuity of Eratosthenes?

Let Us Reflect Direction: Read the situation and answer the reflection question in one to two sentences. Situation: There are still people on Earth who believe that the Earth is flat. Reflection Question: How will you convince them that the Earth is an oblate spheroid and not flat? Check yourself: To help you monitor your progress in using this SLM, check each task in this SLM as to accomplished or not accomplished, easy or hard, and write down who helped you in doing the task. If no one helps you, just write down "on my own." Who helped you?

Remarks Task Accomplished

Not Accomplished

1. 2. 3. 4.

Let Us Try Activity 1 Let us Practice Let us Practice More 5. Let us Assess 6. Let us Enhance 7. Let Us Reflect 9

Easy

Hard

Lesson

2

Astronomical Phenomena Before Telescopes

Before the advent of telescopes, humans already observed astronomical phenomenon. Most of their observation is visible by the naked eyes. Ancient people carve out cosmologies from their direct perspective of the heavens based on philosophical and religious symbols. This lesson will walk you through the astronomical phenomena observed by humans long before the invention of telescopes.

Let Us Study Perform Activity 2 to distinguish astronomical phenomena seen by an unaided eye. Activity 2: Naked Eye vs. Telescopes Direction: Astronomical phenomenon is given in the first column. Check the second column if you can see the said phenomena with your naked eye, and check the third column if you need a telescope for you to see it. Visible to Naked Eye

Astronomical Phenomenon 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

the

Visible with Telescope Only

Phases of the Moon Location of Jupiter's Moon Saturn's Rings Lunar Eclipse Visibility of Pluto The motion of the stars Visibility of the Kuiper Belt Visibility of Mars Solar Eclipse Visibility of Venus

Guide Question: 1. What astronomical phenomena are visible to the eyes? 10

Ancient civilizations already observed the rising and setting of the Sun in the East and West. They knew that the rising and setting of the Sun on the horizon varies every year. About 3000 years ago, the early Babylonian, Assyrian, and Egyptian astronomers estimated the year's length. This was done by carefully keeping track of Sirius's bright star, which can be seen during predawn and has a yearly cycle that resembled the Nile River's flooding. This was also true with the Chinese, whose calendar days were almost the same as the Egyptians. Ancient Chinese also recorded meteors, comets, even dark spots of the Sun. The Mayan culture developed a calendar based on the planet Venus in which they use in deciding to go to war against another tribe or not. In Europe, ancient people observed the motions of the Sun and the Moon by putting them into writings and portraying drawings on the stones. Here are some examples of an astronomical phenomenon that early humans observed: A. Phases of the Moon

The Moon shines because it reflects sunlight from its surface. As the Moon revolves around Earth, different portions of Earth's side are lighted, causing the Moon's appearance to change. Moon phases are the changing appearances of the Moon as seen from Earth. The phase you see depends on the positions of the Moon, Earth, and the Sun. People from the past observed that the Moon changes its path and appearance within 29.5 days. They observed that the Moon changes its appearance from small-arc shaped to a full circular shape. 11

A new moon occurs when the Moon is bet...