Physical Science Module 2 Grade 11 quarter 4 PDF

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Physical ScienceQuarter 2 – Module 2:Examples of AstronomicalPhenomena Before the Advent ofTelescopesPhysical Science Alternative Delivery Mode Quarter 2 – Module 2: Examples of Astronomical Phenomena Before the Advent of Telescopes First Edition, 2020Republic Act 8293, section 176 states that: No c...

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Physical Science Quarter 2 – Module 2: Examples of Astronomical Phenomena Before the Advent of Telescopes

Physical Science Alternative Delivery Mode Quarter 2 – Module 2: Examples of Astronomical Phenomena Before the Advent of Telescopes 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 Secretary: Leonor Magtolis Briones Undersecretary: Diosdado M. San Antonio Development Team of the Module Writers: Jerwin A. Gutierrez Editors: Priscilla D. Domino, Felipa A. Morada Reviewers: Rogelio D. Canuel, Elmer C. Bobis, Felipa A. Morada Illustrator: John Albert Rico Layout Artist: Elsie R. Reyes Pamela A. Lalusin, Mary Grace L. Asa Management Team: Wilfredo E. Cabral, Regional Director Job S. Zape Jr., CLMD Chief Elaine T. Balaogan, Regional ADM Coordinator Homer N. Mendoza, Schools Division Superintendent Catherine V. Maranan, Assistant Schools Division Superintendent Lorna R. Medrano, CID Chief Edita T. Olan, EPS In-charge of LRMS Editha M. Malihan, EPS Printed in the Philippines by ________________________ Department of Education – Region IV-A CALABARZON Office Address: Telefax: E-mail Address:

Gate 2 Karangalan Village, Barangay San Isidro Cainta, Rizal 1800 02-8682-5773/8684-4914/8647-7487 [email protected]/[email protected]

Physical Science Quarter 2 – Module 2: Examples of Astronomical Phenomena Before the Advent of Telescopes

Introductory Message For the facilitator: Welcome to the (Physical Science – Grade 11) Alternative Delivery Mode (ADM) Module on (Examples of Astronomical Phenomena Before the Advent of Telescopes) ! This module was collaboratively designed, developed and reviewed by educators both from public and private institutions to assist you, the teacher or facilitator in helping the learners meet the standards set by the K to 12 Curriculum while overcoming their personal, social, and economic constraints in schooling. This learning resource hopes to engage the learners into guided and independent learning activities at their own pace and time. Furthermore, this also aims to help learners acquire the needed 21st century skills while taking into consideration their needs and circumstances. In addition to the material in the main text, you will also see this box in the body of the module:

Notes to the Teacher This contains helpful tips or strategies that will help you in guiding the learners.

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. Furthermore, you are expected to encourage and assist the learners as they do the tasks included in the module.

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For the learner: Welcome to the Physical Science – Grade 11 - Alternative Delivery Mode (ADM) Module on (Examples of Astronomical Phenomena Before the Advent of Telescopes! The hand is one of the most symbolic parts of the human body. It is often used to depict skill, action and purpose. Through our hands we may learn, create and accomplish. Hence, the hand in this learning resource signifies that as a learner, you are capable and empowered to successfully achieve the relevant competencies and skills at your own pace and time. Your academic success lies in your own hands! This module was designed to provide you with fun and meaningful opportunities for guided and independent learning at your own pace and time. You will be enabled to process the contents of the learning resource while being an active learner. This module has the following parts and corresponding icons: What I Need to Know

This will give you an idea of the skills or competencies you are expected to learn in the module.

What I Know

This part includes an activity that aims to check what you already know about the lesson to take. If you get all the answers correctly (100%), you may decide to skip this module.

What’s In

This is a brief drill or review to help you link the current lesson with the previous one.

What’s New

In this portion, the new lesson will be introduced to you in various ways such as a story, a song, a poem, a problem opener, an activity or a situation.

What is It

This section provides a brief discussion of the lesson. This aims to help you discover and understand new concepts and skills.

What’s More

This comprises activities for independent practice to solidify your understanding and skills of the topic. You may check the answers to the exercises using the Answer Key at the end of the module.

What I Have Learned

This includes questions or blank sentence/paragraph to be filled in to process what you learned from the lesson.

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What I Can Do

This section provides an activity which will help you transfer your new knowledge or skill into real life situations or concerns.

Assessment

This is a task which aims to evaluate your level of mastery in achieving the learning competency.

Additional Activities

In this portion, another activity will be given to you to enrich your knowledge or skill of the lesson learned. This also tends retention of learned concepts.

Answer Key

This contains answers to all activities in the module.

At the end of this module you will also find:

References

This is a list of all sources used in developing this module.

The following are some reminders in using this module: 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 What I Know before moving on to the other activities included in the module. 3. Read the instruction 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 through with it. 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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What I Need to Know

This module was designed and written with you in mind. It is here to help you master the nature of Physical Science. The scope of this module permits it to be used in many different learning situations. The language used recognizes the varied vocabulary level of students. The lessons are arranged to follow the standard sequence of the course. But the order in which you read them can be changed to correspond with the textbook you are now using. The module includes:

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Lesson 2 – Examples of Astronomical Phenomena Before the Advent of Telescopes

After going through this module, you are expected to: 1. 2. 3. 4. 5.

explain what is astronomy; enumerate the examples of astronomical phenomena; describe the phases of the moon; differentiate lunar and solar eclipses; appreciate the importance of astronomical phenomena and how they affect your life.

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What I Know

Choose the letter of the best answer. Write the chosen letter on a separate sheet of paper. 1. What practical value did astronomy offer to ancient civilizations? A. B. C. D.

It helped them understand our cosmic origins. It allowed them to predict eclipses with great accuracy. It helped them find uses for ancient structures like Stonehenge. It helped them keep track of time and seasons, and it was used by some cultures for navigation.

2. Lunar eclipses can occur only during a _________. A. first quarter moon B. full moon C. new moon D. third quarter moon 3. We cannot see a new moon in our sky because _________. A. B. C. D.

no sunlight is illuminating the Moon it is obscured by the Earth's shadow it is above the horizon during the daytime a new moon is quite near the Sun in the sky

4. If we have a new moon today, when will we have the next full moon? A. In about 1 week B. In about 2 weeks C. In about a month D. In about 6 months 5. What do the structures of Stonehenge, the Templo Mayor, the Sun Dagger, and the Big Horn Medicine Wheel all have in common? A. They all can be used as lunar calendars. B. They were all places used for religious sacrifice C. They were all built on the orders of ancient kings. D. They were all used by ancient peoples for astronomical observations.

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6. What is the other name for the star Polaris? A. Andromeda B. Antares C. North Star D. South Star 7. Half of the illuminated disk of the Moon is visible from Earth during the _________ phase of the Moon. A. B. C. D.

first-quarter full Moon gibbous (waning) gibbous (waxing)

8. A(n) ____________ eclipse occurs when the Moon casts its shadow on Earth. A. B. C. D.

lunar sidereal solar umbral

9. A solar eclipse cannot be seen with every new Moon because A. B. C. D.

they occur at night the moon has craters the Moon is not part of a solar eclipse the Moon's orbit is inclined approximately 5 degrees

10. Which of the following is the brightest planet? A. Earth B. Mars C. Mercury D. Venus 11. The largest planet discovered before the invention of telescope is __________ . A. Jupiter B. Neptune C. Uranus D. Venus

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12. It refers to the science of the universe outside of our planet. A. Astrology B. Astronomy C. Geography D. Geology 13. Which of the following is the smallest planet? A. Earth B. Mars C. Mercury D. Venus 14. Which one of the following planets is also called morning star or evening star? A. Earth B. Mars C. Mercury D. Venus 15. In which direction does the Sun rise? A. East B. North C. South D. West

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Lesson

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Examples of Astronomical Phenomena Before the Advent of Telescopes

You will now try to travel to outer space by using your imagination to learn about Astronomy. For thousands of years, humans have looked at the night sky and wondered about the stars. With only the unaided eye, they neither saw nor dreamed that the stars are greater in number than all the grains of sand on all the beaches of the world! Nor did they realize that the sun is a star – simply the nearest star to us in the universe. Probably the most fascinating was the moon, which when full was perceived as a flat circular disk rather than as a three-dimensional sphere we now know it to be.

What’s In

The roots of astronomy reach back to prehistoric times when humans first noted stars in the night sky. The earliest astronomers divided the night sky into groups of stars called constellations. The names of the constellations are mainly a carryover from the names assigned by early Greek, Babylonian and Egyptian astronomers. The grouping of stars and the significance given to them varied from culture to culture. In some cultures, the constellations stimulated story-telling and the creation of great myths. In some cases, the constellations honored great heroes like Hercules and Orion or served as navigational aids for travelers and sailors. On the other hand, some people believe that constellations provided a guide for planting and harvesting crops for they were seen to move periodically in the sky, in concert with the seasons. Charts of these periodic movements became some of the first calendars. Stars were thought to be points of light on great revolving celestial sphere having the earth as its center. Positions of the sphere were believed to affect earthly events and so were carefully measured. Keen observations and logical reasoning gave birth to both Astrology and later, to Science.

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Notes to the Teacher This lesson is just an introduction to astronomy. This is more on the astronomical phenomena before the advent of the telescopes. Modern instruments used by astronomers like the optical, reflecting, refracting, orbiting and space telescopes are not yet included in this lesson. Uranus and Neptune are also not included in this lesson since they were discovered only when the telescopes are present. Uranus, the smallest of the giant planets, is much fainter than Saturn. It was not discovered until 1781. After that, scientists kept track of the positions of Uranus which did not move in exactly the way they expected it to. Perhaps there was another planet farther out, pulling on Uranus and changing its orbit. Finally, in 1846, after many years of difficult work, this “planet X” was found, and Neptune joined the family of the solar system. It is a very distant family, being some 30 times as far from the sun as the Earth is. On this account, we know very little about Neptune except that it is cold. From Neptune, the sun must look only like a very bright but distant star. Because it receives so little heat from the sun, Neptune has a very low temperature of -167.78° Celsius.

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What’s New

Astronomy Defined Astronomy is the science of the universe outside of our planet. This is the branch of physical science dealing with heavenly bodies. It has resulted in many practical inventions, ideas, including calendars, navigational techniques, laws of motion, engineering of products and an increased understanding of energy and weather.

Some Astronomical Terms for Students Moon: A natural object that orbits a larger object. Eclipse: when one celestial body such as a moon or planet moves into the shadow of another celestial body. Solar eclipse: a type of eclipse that occurs when the Moon passes between the Sun and Earth, and the Moon fully or partially blocks the light from the Sun. Lunar Phase: one of the cyclically recurring apparent forms of the moon Gibbous: the figure of the moon that is more than half full, looking swollen on one side Crescent: the figure of the moon that appears as a curve with pointy ends Waxing: growing; describes the moon when the illuminated portion is increasing Waning: shrinking; describes the moon when the illuminated portion is decreasing Planet: In the solar system, a planet is a large round object that orbits the Sun and has cleared out most of the other objects in its orbit. Solar System: The Sun and all of the planets, comets, etc. that revolve around it.

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What is It

Even before the advent of the telescopes, ancient astronomers were able to observe the following:

1. 2. 3. 4. 5. 6.

rising and setting of the Sun in the east and the west, respectively, point where the Sun rises and sets in the horizon varies in a year, phases of the moon, lunar eclipse, solar eclipse, daily and annual motion of the stars, and 7. planets Mercury, Venus, Mars, Jupiter, and Saturn.

Rising and Setting of the Sun 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.

Figure 1: The figure shows the ancient stele used as a gnomon, a primitive version of sundial

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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. We described the movement of stars in the night sky, but what about during the daytime? The stars continue to circle during the day, but the brilliance of the Sun makes them difficult to see. (The Moon can often be seen in the daylight, however.) On any given day, we can think of the Sun as being located at some position on the hypothetical celestial sphere. When the Sun rises —that is, when the rotation of Earth carries the Sun above the horizon—sunlight is scattered by the molecules of our atmosphere, filling our sky with light and hiding the stars above the horizon. For thousands of years, astronomers have been aware that the Sun does more than just rise and set. Have you ever given much thought to sunrises and sunsets? Wouldn't it be great if the Sun rose every morning at the same time? Wouldn't you enjoy the convenience of knowing exactly when the Sun would set at the same time each night? Unfortunately, the world doesn't work that way. If you live in North America, you probably look forward to those long summer days when you can play outside for hours on end because the Sun doesn't set until late in the evening. Likewise, you might dread short winter days. You get up for school before the Sun rises and then you barely have any time to play after school and do homework before it gets dark. Things would be different if: (1) Earth orbited the Sun in a perfect circle; and (2) Earth's axis was perpendicular to the plane of its orbit (straight up and down). If that were the case, the Sun would rise and set at the same times every day. It would also take the same path across the sky every day of the year. However, neither of those conditions is true for Earth. Instead of a perfectlycircular orbit, Earth's orbit around the Sun is slightly elliptical. This means that the Sun travels across the sky at slightly different speeds from day to day depending upon where Earth is in its orbit. Earth's axis is also not perpendicular to the plane of its orbit. Instead, Earth is tilted on its axis approximately 23.4°. This is what gives us our seasons here on Earth. When the North Pole is tilted toward the Sun, the Northern Hemisphere experiences summer, and the Sun is high in the sky at noon. During the winter, the North Pole is tilted away from the Sun, and at noon the Sun doesn't get nearly as high in the sky.

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Earth's tilt also explains why the longest day of the year occurs on the summer solstice (usually around June 21). Likewise, the shortest day of the year occurs on the winter solstice (usually around December 21). The combination of Earth's elliptical orbit and the tilt of its axis results in the Sun taking different paths across the sky at slightly different speeds each day. This gives us different sunrise and sunset times each day. Once the summer solstice passes, you'll notice the days begin to get shorter each day. This trend continues until the winter solstice, the shortest day of the year. After the winter solstice, days get slightly longer each day up until the summer solstice, and the process repeats year after year. It changes position gradually on the celestial sphere, moving each day about 1° to the east relative to the stars. Very reasonably, the ancients thought this meant the Sun was slowly moving around Earth, taking a period of time we call 1 year to make a full circle. Today, of course, we know it is Earth that is going around the Sun, but the effect is the same: the Sun’s position in our sky changes day to day. We have a similar experience when we walk around a camp...