Republic of the Philippines

Department of Education Regional Office IX, Zamboanga Peninsula

Science Grade 8

Quarter 2 - Module 6 Comets, Asteroids, and

Meteors

Zest for Progress

Zeal of Partnership

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Name of Learner: ___________________________

Grade & Section: ___________________________

Name of School: ___________________________

What I need to know

This module was designed to help you master the concepts behind Comets,

Asteroids and Meteors. The scope of this module permits it to be used in many

different learning situations. The language used recognizes the diverse 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.

After going through this module, you are expected to:

1. Compare and contrast comets, meteors and asteroids (S8S-IIg-22)

Furthermore, you should be able to accomplish the following subtasks:

2. distinguish the differences between a comet and an asteroid;

3. identify the characteristics of a meteoroid, meteor and meteorite;

4. describe the scientific basis behind superstitions about comets, asteroids and

meteors;

What I need to know In this module, we will learn about celestial objects or NEO (Near Earth Objects) hovering above our Earth’s atmosphere but before getting into the topic, do you still remember your lesson about the layers of the atmosphere in grade 7? If so, let us test your prior knowledge.

Module

6

Comets, Asteriods, and Meteors

Activity 1.1 Layers of the Atmosphere

Directions: Below is an illustration of the Earth’s atmosphere. Label the layer of the

atmosphere that corresponds to Exosphere, Troposphere, Stratosphere,

Thermosphere and Mesosphere. Write your answer in the box provided below.

In the previous activity, you were reminded about the composition and what’s

inside the Earth’s atmosphere. It’s now time for you to know about celestial bodies

beyond our atmosphere.

What’s In

Activity 1.2: Care to say something?

In the next page are three photos describing the impact of Near-Earth Objects

(NEO) or extra-terrestrial bodies in the solar system.

Give a brief explanation on what do you think is happening in each picture and write it

down in the appropriate column.

5

Describe what you see

What do you think are its impacts towards Earth?

Activity 1.3. Who am I?

Directions: Label each picture correctly. Is it a meteorite, meteoroid or a meteor?

(5 pts each)

1.____________________ 2.___________________ 3.__________________

comet

15

Activity 1.4. Superstitious or Fact?

Directions. The following sentences below are statements and descriptions

regarding celestial objects in our solar system. Write Superstitious, if you think that

the statement is just a myth or make believe. Write Fact if you think that the

statement is backed up by scientific evidence. Write your answer in the space

provided below.

________1. Meteors were caused by witches.

________2. A comet entering Earth is extremely dangerous.

________3. You only wish on a shooting star so that your dreams will come true.

________ 4. A meteorite once caused the extinction of dinosaurs million years ago.

________ 5. A comet approaching the Earth signifies that world war 3 is coming.

What is It

How did you find the previous activities? If your answers are related to comets,

asteroids, craters, meteors and even shooting stars, and you know a thing or two about

superstitious beliefs mentioned above, then congratulations, you are on your way

towards awesome learning!

Look up in the sky! It’s a comet!

Comets and asteroids are referred to by astronomers as Near-Earth Objects

(NEO). Comets are icy bodies or objects while asteroids are rocky fragments. They

are remnants from the formation of our solar system 4.6 billion years ago

Comets and asteroids have irregular shapes and varied sizes. They both reflect

light from the sun in varying amounts depending on the size and composition. The

presence of more silicates allows a comet or asteroid to reflect light.

Comets and asteroids both orbit around the sun. This means, you can see a

comet for up to a year in the night sky. The major difference is their origin or where

they came from in space.

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Comets usually come from the Oort Cloud which is beyond our solar system,

and a few from Kuiper Belt, which is just beyond Neptune’s orbit. Long period

comets come from the Oort Cloud while short period comets come from the

Kuiper Belt ( as seen in Figure 1).Comet Halley, the most famous short period comet

in the 20th century, can be seen in the sky every time it makes its nearest approach to

the sun. It orbits the sun for around 75-79 years.

Figure 1. Location of Kuiper Belt and Oort Cloud (Photo grabbed from NASA space place)

Asteroids, on the other hand, originate from the Main Asteroid Belt between

Mars and Jupiter. This belt is theorized by scientists to be remnants of a planet that

did not completely form. The orbit of an asteroid is more rounded and elliptical than

the orbit of a comet. In February 2013, Asteroid 2012 DA14 made a very close

approach to Earth as it orbited the sun. It is the closest that any asteroid has ever been

to Earth. In December 2012, during the midst of the doomsday prophecies, Asteroid

Toutatis also made a near approach to Earth but not as close as Asteroid 2012 DA14.

Another difference between a comet and an asteroid is their chemical

composition. Sometimes, a comet may contain other elements like sodium or argon

while asteroid is mostly composed of rock (silicates) and metals (iron and nickel being

the usual metals)

The composition of a comet is important in helping scientists understand how

Earth has liquid water, making our planet liveable. They believed that the early impact

of comets on Earth brought liquid water to the planet. The chemical composition of

Asteroid helps provide clues for scientists in discovering the chemical composition of

the Earth since asteroids are mostly composed of metals like iron and nickel, the same

metals that make up Earth’s core. The table 1 below summarizes the similarities and

differences of a comet and asteroid:

Table 1: Comparison of a comet and an asteroid

Characteristic Comet Asteroid

Origin Oort cloud and Kuiper Belt Main Asteroid Belt

Shape Varied/Irregular Varied/Irregular

Size range diameter 1-10 (nucleus only) 1- 100

Chemical composition Ice (frozen water);frozen gases (ammonia, methane and carbon dioxide); other organic compounds

Silicates, iron, nickel

Orbit Highly elliptical More rounded

Orbital period (years) 75 – 100,000 plus 1-100

Comets and asteroids orbit around the sun, but it is theorized by scientists that other planets in our solar system can influence and alter the orbital path of these NEOs, thus they come crashing towards Earth. It is important for scientists to study the orbital periods of these NEOs to be able to tell when these objects would make their closest appearance near the Earth and predict the likelihood of NEOs collision with the Earth. While asteroids and comets have collided with Earth in the past, the frequency is very much longer than a human lifetime, so there is no need to worry for now.

How about meteor showers? Are comets and meteors the same?

You have probably seen a shooting star in the night sky, right? That streak of light you see in the atmosphere which seems to appear falling on the ground, is called a meteor. Truth be told, meteors that look like “shooting stars” are not stars at all. In fact, a meteor is a light phenomenon that occurs when a meteoroid burns up as it enters the earth’s atmosphere. A meteoroid is a broken up rock and dust from either a comet, asteroid, the Moon or from Mars. A meteoroid becomes a meteor when it falls through the atmosphere, and we see it shoot across the sky.

How are a meteor, meteoroid and meteorite related?

You already know that meteoroid can come from a comet or an asteroid.

Meteoroids, which are made from dust and fragments of a comet, hurl through the

atmosphere so fast that they heat and actually burn very brightly. We then observe

many streaks of light from the night sky which is called meteors. When Earth’s orbit

passes through a trail of comet debris, there are many meteors visible in a single

night – a phenomenon called meteor shower. But every now and then, large

meteors make it all the way to the Earth’s atmosphere, and fall to the ground (Earth’s

crust) – then they are called meteorites. Figure 2 below summarizes the

characteristics of a meteoroid, meteor and meteorite.

Figure 2. Journey of a meteor (Photo grabbed from taylorsciencegeeks.weebly)

Meteorites entering the Earth’s crust are of importance to scientists in studying the occurrence of different elements and compounds on Earth. Through this information, mineral resources are being carefully studied and analysed. There are three types of meteorites: stony, stony-iron and iron meteorites. In the Philippines, there are only five internationally accepted meteorites summarized in the table 2 below:

Table 2: Meteorites discovered in the Philippines

Meteorite Year of discovery

Place discovered

Type Chemical composition

Pampanga 1859 Pampanga stony Iron, nickel

Paitan 1910 Ilocos stony Iron, magnesium

Calivo 1916 Western Visayas

stony Not determined

Pantar 1938 Central Mindanao

stony Iron, magnesium iron silicate

Bondoc 1956 Southern Tagalog

iron Metallic iron nickel

As you can see from the table, the meteorites found in our ground are very rich

in mineral resources. The presence of these meteorites and impact craters hold much

potential for the mining industry aside from being objects of scientific scrutiny.

What’s More

Activity 1.5: Compare and contrast.

You have now learned the different characteristics of a comet and an asteroid.

Let us now test your knowledge!

Directions: Use the Venn diagram below to make a comparison between a comet

and an asteroid. Write characteristics that only a comet possesses in the left side of

the circle and characteristics of an asteroid on the right side. Write the similarities of a

comet and an asteroid in the center circle. Choose your answers from the word bank

provided for you below.

COMET ASTEROID

BOTH

COMET AND

ASTEROID

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In the previous activity, you were able to compare comets and asteroids. This

time, let us test your newly acquired knowledge on the differences between a

meteor, meteoroid, and meteorite.

Activity 1.6. Draw me the symbol

Directions: Show where a meteoroid, meteor, and meteorite are most likely to be

found in the diagram below. (5 points for every correct symbol)

Use the following symbols for each:

meteor;

meteoroid;

meteorite

Activity 1.7 True or False.

Directions: Below is a passage/article about comets, asteroids and meteors. Encircle

the underlined words if you think that the sentences are factual. If the

phrase/statement is false, put an X mark on the underlined word and write the

correct word above it. (2 points each)

Example:

Earth is the only livable planet in the solar system.

3rd Earth is the 4th planet from the Sun.

Venn Diagram Word bank

Varried/Irregular shape a type of NEO Highly elliptical

Made from icy objects comes from Oort cloud more rounded orbit

Made from rocky fragments comes from Asteroid belt made from silicates

Orbits the sun comes from Kuiper Belt “leftovers” from solar system

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1. Most of the asteroids in the solar system orbit the sun between Jupiter and Mars in

an area known as the Kuiper Belt.

2. Comet Hailey makes its nearest approach to Earth every 75-59 years.

3. Sometimes, tiny bits of asteroids reach the Earth’s atmosphere and burn up, leaving

a bright trail called meteor.

4. Meteoroids are meteors that strike the earth.

5. Five meteorites were discovered in the Philippines.

Activity 1.8 Who Am I?

You are now becoming a pro! You have already completed activities in distinguishing

different types of Near Earth Objects (NEO). Let us further test your capabilities and

answer the activity below:

Directions: You are to identify whether the description below matches that of a

comet, asteroid or a meteor. Put a check to all the boxes that apply.

Comet Asteroid

Meteor

Forms belt between Jupiter and Mars

Orbits around the sun

also called “shooting stars”

Found in the Oort cloud and Kuiper belt

Usually burn up in the atmosphere

Ball of gas and dust

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What I Have Learned

What I Can Do

Activity 1.9 Superstitious beliefs!

Congratulations! You are now equipped with the necessary skills and knowledge about

the characteristics of celestial bodies in space. But did you know that in the early days

even until now, NEOs are associated with superstitious beliefs that had impacted and

influenced the society’s way of living? Let us investigate further!

Directions: Make an argumentative essay about superstitions related to comets and

asteroids. Gather at least 3 superstitions through the internet, or by interviewing your

parents and elders in your house. List down as many scientific evidences that support

the said superstitions. Last but not the least, propose doable actions that you can do

to promote a more scientific attitude towards comets, asteroids, and meteors to your

fellow students or to family members. The given rubrics below will be used for scoring

the essay:

Argumentative essay rubrics:

4 3 2 1

MAIN POINTS 3 main points

are well

developed with

supporting

details

3 main points

are present but

may lack detail

and

development

3 main points

are present but

all lacks

development

Less than 3 main

points with poor

development of

ideas

ORGANIZATION Very well

organized and

informative

Clear words are

used

Some pieces of

information are

not clear and is

hard to follow

Arrangement of

essay is unclear

and illogical

Have you learned something valuable from this week’s module? If so, share to me the

things you found interesting in this lesson.

I am interested in learning about comparing comets, asteroids and meteors

First I know that comets are _______________________

Second I know that asteroids are______________________

Finally, I know that meteoroids are____________________

Now you know something that I know about _________________________

MECHANICS Sentence

structure is

correct.

Punctuation and

capitalization is

correct

Sentence

structure is

generally

correct. One or

two errors in

punctuation and

capitalization

Work contains

structural

weaknesses and

grammatical

errors

Work contains

multiple incorrect

sentence

structures

Assessment

Directions. Encircle the letter of the correct answer.

1. What do asteroids and comets have in common?

a. They both orbit the sun.

b. They both have the same shapes and sizes.

c. They both have the same orbital radius.

d. They have nothing in common

2. Why do asteroids and comets differ in position?

a. Asteroids formed inside the frost line, while comets formed outside

b. Asteroids and comets formed at different times

c. Comets are much larger than asteroids

d. Asteroids are much larger than comets

3. The following choices below are characteristics of an asteroid EXCEPT;

a. Has varied/irregular shape c. It orbits around the sun

b. Found in the Kuiper belt d. Composed of rocky fragments

4. Where is the asteroid belt located?

a. Just outside the solar system

b. In between the Sun and the Earth

c. In between Mars and Jupiter

d. Just beside the pluto

5. Which of the description below best defines what a comet is?

a. Smallest dwarf planets

b. Shooting stars that emit light

c. Icy objects in the space

d. Rocky fragments of dust

6. Which of the following statements about comet is correct?

a. Comets come from rocky fragments that are said to be remnants of a

planet

b. It is a streak of light that passes and falls to the Earth’s surface

c. Comets are mainly located in between Mars and Jupiter

d. They can be found in the Kuiper Belt and Oort Cloud

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7. What do you call the most famous comet of the 20th century which is visible

from Earth every 75-76 years.

a. Comet Hale bopp b. Comet Halley c. Comet Hailey d. Comet Hell

8. Where are long period comets usually located?

a. Kuiper Belt b. Oort Cloud c. Asteroid Belt d. Moon

9. Where are short period comets usually located?

a. Kuiper Belt b. Oort cloud c. Asteroid belt d. Moon

10. The main asteroid belt lies in between the orbits of ___________.

a. Earth and Mars

b. Saturn and Jupiter

c. Venus and Earth

d. Mars and Jupiter

11. How do a meteoroid and a meteorite differ in terms of location?

a. Meteoroids are far up in the sky, while meteorites have already landed on

Earth

b. Meteorites are far up in the sky, while meteoroids have already landed on

Earth

c. Meteorites emit light while meteoroids emit lightning speed

d. Meteoroids emit light while meteorites emit lightning speed

12. What is a meteorite?

a. A streak of light caused by a star passing by in the night sky

b. A small moon that orbits one of the giant planets

c. A fragment from an asteroid that falls on the earth’s surface

d. A streak of light caused by a small particle from space burning up in the

Earth’s atmosphere

13. All of the choices below are the three types of meteorites EXCEPT;

a. Stony b. Stony-iron c. Stony d. Iron

14. What is a meteor?

a. A shooting star in the night sky emitting light

b. A fragment of the sun heading towards Earth

c. Group of stars entering Earth’s atmosphere

d. A light emitted by a space rock burning towards Earth’s atmosphere

15. What is a meteor shower?

a. A piece of rock entering Earth’s crust

b. A ball of large icy fragment orbiting around the sun

c. It happens when Earth’s orbit passes through a trail of comet debris

d. Group of stars falling and passing through the earth’s atmosphere

Additional Activities

By now, you already have all the information in comparing Comets,

Asteroids and Meteors. To further enrich your knowledge, answer the

activity below.

Activity 1.10 Fill me up!

Directions: Supply the missing letters to complete the word/s that is

being described below.

1. Comets can be usually found in the Oort Cloud. Few comets can also be found in which part of the Solar System?

___ ___ ___ P ___ R ___ E ___ T

2. An extraterrestrial body that has a shorter orbital period.

A ___ ___ E R ___ I ___

3. When a meteoroid passes through Earth’s atmosphere and burns up in the process

___ E ___ E ___ R

4. What celestial objects can a meteoroid come from?

__ O __ E __ , A __ S T __ R __ I D

5. It happens when the Earth intersects a comet’s path and moves through the stream of debris and dust emitted by the comet.

M __ T __ __ R S __ O __ E __

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References

Books: Department of Education. (2013) Grade 8 learner’s module. Department of Education Madriaga, E.A.,

Valdoz, M.P., Aquino, M.D., & Castillo, M.A.B. (2015)

Website: The Comet’s tale: Their Place in Space http://cse.ssl.berkeley.edu/segwayed/lessons/cometstale/frame_place.html Meteors, Meteoroids, and Meteorites http://www.pibburns.com/catastro/meteors.htm#meteorshowers NASA: Space Place, Explore Earth and Space https://spaceplace.nasa.gov/comet-ocean/en/ Meteorites Facts https://universavvy.com/meteorites-facts

Development Team Region IX Hymn

Writer: Vanessa Joy L. Tomboc Editors: Margie Lou C. Jacob

Laarni A. Adonis Kathleen Joy B. Padilla Joly C. Baradero

Reviewer: Sandy R. Albarico Illustrator: Layout Artist: Management Team:

Majarani M. Jacinto, CESO VI SDS-ZDS

Visminda Q. Valde, Ed.D

ASDS

Raymond M. Salvador, Ed.D ASDS

Juliet A. Magallanes, Ed.D

CID Chief

Florencio R. Caballero, DTE EPS-LRMDS

Sandy R. Albarico EPS I-Science

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Land.

Answer Key-Gr8Q2W6 Science

What’s more Activity 1.5 Compare and Contrast Comet -made from icy objects -comes from Oort Cloud - comes from Kuiper Belt - highly elliptical Asteroid Made from rocky fragments More rounded orbit Comes from asteroid belt Made from silicates Both Varied/irregular shape A type of NEO Orbits the sun “leftovers” from the solar system

Activity 1.6 Draw me the symbol

Activity 1.7 True or

False

1.Asteroid Belt 2.Comet Halley 3.Meteor 4.Meteorite 5.Five

Activity 1.8 Who Am I?

Comet Asteroid Meteor

Forms belt between Jupiter and Mars

Orbits around the sun

also called “shooting stars”

Found in the Oort cloud and Kuiper belt

Usually burn up in the atmosphere

Ball of gas and dust

Activity 1.10 Fill me

Up!

1.KUIPER BELT

2.ASTEROID 3.METEOR 4.COMET,

ASTEROID 5.METEOR

SHOWER

What I Know

1.D 14.C 2.B 15. A 3.A 4.D 5.C 6.C 7.D 8.A 9.B 10.A 11.D 12.C 13.B 14.C 15.A

Assessment

1.A 8.B 15. C

2.A 9.A

3.B 10.D

4.C 11. A

5.C 12. D

6.D 13. C

7.B 14. D

What's IN Answers are in order from top to bottom

1.troposphere 2.stratosphere 3.mesosphere 4.thermosphere 5.Exosphere

Activity 1.3 1.meteor 2.meteorite 3.meteoroid

Activity 1.4 1.Superstitious 2.Fact 3.Superstitious 4.Fact 5.Superstitious